diff --git a/IMPLEMENTATION_SUMMARY.md b/IMPLEMENTATION_SUMMARY.md
deleted file mode 100644
index 17d555c..0000000
--- a/IMPLEMENTATION_SUMMARY.md
+++ /dev/null
@@ -1,142 +0,0 @@
-# Implementation Summary: Timezone Fix + Per-Space Settings
-
-## Overview
-Fixed timezone display issues and added per-space scheduling settings to the space booking system.
-
-## Changes Implemented
-
-### Part A: Frontend Timezone Fix ✅
-
-**File: `frontend/src/utils/datetime.ts`**
-- Added `ensureUTC()` function to handle naive datetime strings from backend
-- Applied `ensureUTC()` to all `new Date()` calls in:
-  - `formatDateTime()`
-  - `formatTime()`
-  - `formatDateTimeWithTZ()`
-  - `isoToLocalDateTime()`
-
-**File: `frontend/src/views/Dashboard.vue`**
-- Imported `ensureUTC` from utils
-- Applied to booking date comparisons in `upcomingBookings` computed property
-
-**Impact:** MyBookings now correctly shows times in user's timezone (e.g., 10:00-17:00 Bucharest instead of 08:00-15:00 UTC).
-
----
-
-### Part B: Per-Space Scheduling Settings (Database) ✅
-
-**File: `backend/app/models/space.py`**
-- Added 4 nullable columns:
-  - `working_hours_start` (Integer)
-  - `working_hours_end` (Integer)
-  - `min_duration_minutes` (Integer)
-  - `max_duration_minutes` (Integer)
-
-**File: `backend/app/schemas/space.py`**
-- Added 4 optional fields to `SpaceBase` and `SpaceResponse`
-
-**File: `backend/migrations/004_add_per_space_settings.sql`**
-- Created migration (already applied to database)
-
-**Impact:** Spaces can now override global settings. NULL = use global default.
-
----
-
-### Part C: Timezone-Aware Validation ✅
-
-**File: `backend/app/services/booking_service.py`**
-- Imported `Space` model and timezone utilities
-- Added `user_timezone` parameter to `validate_booking_rules()`
-- Load per-space settings with fallback to global
-- Convert UTC times to user timezone for working hours validation
-- Fix max bookings per day to use local date boundaries
-
-**File: `backend/app/api/bookings.py`**
-Updated 6 endpoints to pass `user_timezone`:
-
-1. **POST /bookings (create)** - Line ~251
-2. **POST /bookings/recurring** - Line ~376
-   - Also fixed: Now converts local times to UTC before storage
-3. **PUT /bookings/{id} (update)** - Line ~503
-4. **PUT /admin/.../approve** - Line ~682
-   - Uses booking owner's timezone
-5. **PUT /admin/.../update** - Line ~865
-   - Uses booking owner's timezone
-6. **PUT /admin/.../reschedule** - Line ~1013
-   - Uses booking owner's timezone
-
-**Impact:**
-- Working hours validation now uses user's local time (9:00 Bucharest is valid, not rejected as 7:00 UTC)
-- Per-space settings are respected
-- Recurring bookings now store correct UTC times
-
----
-
-### Part D: Admin UI for Per-Space Settings ✅
-
-**File: `frontend/src/views/Admin.vue`**
-- Added form section "Per-Space Scheduling Settings"
-- Added 4 input fields with placeholders indicating global defaults
-- Updated `formData` reactive object
-- Updated `startEdit()` to load space settings
-- Updated `resetForm()` to clear settings
-- Added CSS for form-section-header, form-row, and help-text
-
-**File: `frontend/src/types/index.ts`**
-- Extended `Space` interface with 4 optional fields
-
-**Impact:** Admins can now configure per-space scheduling rules via UI.
-
----
-
-## Testing Checklist
-
-### Timezone Display
-- [ ] User with `Europe/Bucharest` timezone sees correct local times in MyBookings
-- [ ] Booking created at 09:00 Bucharest shows as 09:00 (not 07:00)
-
-### Working Hours Validation
-- [ ] Booking at 09:00 Bucharest (07:00 UTC) is accepted (not rejected by 8-20 rule)
-- [ ] User sees error message with correct timezone-aware hours
-
-### Per-Space Settings
-- [ ] Create space with custom working hours (e.g., 10-18)
-- [ ] Booking outside custom hours is rejected
-- [ ] Space without settings uses global defaults
-- [ ] Admin UI displays and saves per-space settings correctly
-
-### Recurring Bookings
-- [ ] Recurring bookings now store correct UTC times
-- [ ] Bookings created for multiple occurrences have consistent timezone handling
-
----
-
-## Files Modified
-
-| # | File | Changes |
-|---|------|---------|
-| 1 | `frontend/src/utils/datetime.ts` | Added `ensureUTC()` + applied to 4 functions |
-| 2 | `frontend/src/views/Dashboard.vue` | Import and use `ensureUTC` |
-| 3 | `backend/app/models/space.py` | Added 4 nullable columns |
-| 4 | `backend/app/schemas/space.py` | Added 4 optional fields |
-| 5 | `backend/migrations/004_add_per_space_settings.sql` | DB migration (applied) |
-| 6 | `backend/app/services/booking_service.py` | Timezone-aware validation |
-| 7 | `backend/app/api/bookings.py` | Updated 6 callers + recurring fix |
-| 8 | `frontend/src/views/Admin.vue` | Admin UI for per-space settings |
-| 9 | `frontend/src/types/index.ts` | Extended Space interface |
-
----
-
-## Known Limitations
-
-1. **SQLite**: COMMENT ON COLUMN not supported (documented in migration file)
-2. **Backward Compatibility**: Existing bookings created before fix may have incorrect times (data migration not included)
-
----
-
-## Next Steps
-
-1. Run frontend ESLint: `cd frontend && npx eslint src/utils/datetime.ts src/views/Dashboard.vue src/views/Admin.vue`
-2. Run backend tests: `cd backend && pytest` (if tests exist)
-3. Manual testing per checklist above
-4. Consider data migration for existing bookings if needed
diff --git a/frontend/package-lock.json b/frontend/package-lock.json
index d8dc730..f8d6c4b 100644
--- a/frontend/package-lock.json
+++ b/frontend/package-lock.json
@@ -15,6 +15,7 @@
         "@fullcalendar/vue3": "^6.1.0",
         "axios": "^1.6.0",
         "chart.js": "^4.5.1",
+        "lucide-vue-next": "^0.563.0",
         "pinia": "^2.1.0",
         "vue": "^3.4.0",
         "vue-router": "^4.2.0"
@@ -2769,6 +2770,15 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/lucide-vue-next": {
+      "version": "0.563.0",
+      "resolved": "https://registry.npmjs.org/lucide-vue-next/-/lucide-vue-next-0.563.0.tgz",
+      "integrity": "sha512-zsE/lCKtmaa7bGfhSpN84br1K9YoQ5pCN+2oKWjQQG3Lo6ufUUKBuHSjNFI6RvUevxaajNXb8XwFUKeTXG3sIA==",
+      "license": "ISC",
+      "peerDependencies": {
+        "vue": ">=3.0.1"
+      }
+    },
     "node_modules/magic-string": {
       "version": "0.30.21",
       "resolved": "https://registry.npmjs.org/magic-string/-/magic-string-0.30.21.tgz",
diff --git a/frontend/package.json b/frontend/package.json
index 84ca054..29a44b1 100644
--- a/frontend/package.json
+++ b/frontend/package.json
@@ -17,6 +17,7 @@
     "@fullcalendar/vue3": "^6.1.0",
     "axios": "^1.6.0",
     "chart.js": "^4.5.1",
+    "lucide-vue-next": "^0.563.0",
     "pinia": "^2.1.0",
     "vue": "^3.4.0",
     "vue-router": "^4.2.0"
diff --git a/frontend/src/App.vue b/frontend/src/App.vue
index 3521bd8..4e6196c 100644
--- a/frontend/src/App.vue
+++ b/frontend/src/App.vue
@@ -1,34 +1,29 @@
 <template>
   <div id="app">
-    <header v-if="authStore.isAuthenticated" class="header">
-      <div class="container">
-        <h1>Space Booking</h1>
-        <nav>
-          <router-link to="/dashboard">Dashboard</router-link>
-          <router-link to="/spaces">Spaces</router-link>
-          <router-link to="/my-bookings">My Bookings</router-link>
-          <router-link v-if="authStore.isAdmin" to="/admin">Spaces Admin</router-link>
-          <router-link v-if="authStore.isAdmin" to="/users">Users Admin</router-link>
-          <router-link v-if="authStore.isAdmin" to="/admin/pending">Pending Requests</router-link>
-          <router-link v-if="authStore.isAdmin" to="/admin/settings">Settings</router-link>
-          <router-link v-if="authStore.isAdmin" to="/admin/reports">Reports</router-link>
-          <router-link v-if="authStore.isAdmin" to="/admin/audit-log">Audit Log</router-link>
+    <AppSidebar v-if="authStore.isAuthenticated" />
 
+    <div class="app-main" :class="{ 'with-sidebar': authStore.isAuthenticated, 'sidebar-collapsed': collapsed }">
+      <!-- Mobile header bar -->
+      <div v-if="authStore.isAuthenticated" class="mobile-header">
+        <button class="mobile-hamburger" @click="toggleMobile" aria-label="Open menu">
+          <Menu :size="22" />
+        </button>
+        <span class="mobile-title">Space Booking</span>
+        <div class="mobile-actions">
           <!-- Notification Bell -->
           <div class="notification-wrapper">
             <button @click="toggleNotifications" class="notification-bell" aria-label="Notifications">
-              <svg width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2">
-                <path d="M18 8A6 6 0 0 0 6 8c0 7-3 9-3 9h18s-3-2-3-9"></path>
-                <path d="M13.73 21a2 2 0 0 1-3.46 0"></path>
-              </svg>
-              <span v-if="unreadCount > 0" class="badge">{{ unreadCount }}</span>
+              <Bell :size="20" />
+              <span v-if="unreadCount > 0" class="notification-badge">{{ unreadCount }}</span>
             </button>
 
             <!-- Notification Dropdown -->
             <div v-if="showNotifications" class="notification-dropdown" ref="dropdownRef">
               <div class="notification-header">
                 <h3>Notifications</h3>
-                <button @click="closeNotifications" class="close-btn">&times;</button>
+                <button @click="closeNotifications" class="close-btn">
+                  <X :size="18" />
+                </button>
               </div>
 
               <div v-if="loading" class="notification-loading">Loading...</div>
@@ -51,14 +46,13 @@
               </div>
             </div>
           </div>
-
-          <button @click="logout" class="btn-logout">Logout ({{ authStore.user?.email }})</button>
-        </nav>
+        </div>
       </div>
-    </header>
-    <main class="main">
-      <router-view />
-    </main>
+
+      <main class="content">
+        <router-view />
+      </main>
+    </div>
   </div>
 </template>
 
@@ -67,10 +61,14 @@ import { ref, computed, onMounted, onUnmounted } from 'vue'
 import { useAuthStore } from '@/stores/auth'
 import { useRouter } from 'vue-router'
 import { notificationsApi } from '@/services/api'
+import { useSidebar } from '@/composables/useSidebar'
 import type { Notification } from '@/types'
+import AppSidebar from '@/components/AppSidebar.vue'
+import { Menu, Bell, X } from 'lucide-vue-next'
 
 const authStore = useAuthStore()
 const router = useRouter()
+const { collapsed, toggleMobile } = useSidebar()
 
 const notifications = ref<Notification[]>([])
 const showNotifications = ref(false)
@@ -83,17 +81,11 @@ const unreadCount = computed(() => {
   return notifications.value.filter((n) => !n.is_read).length
 })
 
-const logout = () => {
-  authStore.logout()
-  router.push('/login')
-}
-
 const fetchNotifications = async () => {
   if (!authStore.isAuthenticated) return
 
   try {
     loading.value = true
-    // Get all notifications, sorted by created_at DESC (from API)
     notifications.value = await notificationsApi.getAll()
   } catch (error) {
     console.error('Failed to fetch notifications:', error)
@@ -114,18 +106,15 @@ const closeNotifications = () => {
 }
 
 const handleNotificationClick = async (notification: Notification) => {
-  // Mark as read
   if (!notification.is_read) {
     try {
       await notificationsApi.markAsRead(notification.id)
-      // Update local state
       notification.is_read = true
     } catch (error) {
       console.error('Failed to mark notification as read:', error)
     }
   }
 
-  // Navigate to booking if available
   if (notification.booking_id) {
     closeNotifications()
     router.push('/my-bookings')
@@ -147,25 +136,20 @@ const formatTime = (dateStr: string): string => {
   return date.toLocaleDateString()
 }
 
-// Click outside to close
 const handleClickOutside = (event: MouseEvent) => {
+  const target = event.target as HTMLElement
   if (
     dropdownRef.value &&
-    !dropdownRef.value.contains(event.target as Node) &&
-    !(event.target as HTMLElement).closest('.notification-bell')
+    !dropdownRef.value.contains(target) &&
+    !target.closest('.notification-bell')
   ) {
     closeNotifications()
   }
 }
 
 onMounted(() => {
-  // Initial fetch
   fetchNotifications()
-
-  // Auto-refresh every 30 seconds
   refreshInterval = window.setInterval(fetchNotifications, 30000)
-
-  // Add click outside listener
   document.addEventListener('click', handleClickOutside)
 })
 
@@ -178,64 +162,68 @@ onUnmounted(() => {
 </script>
 
 <style scoped>
-.header {
-  background: #2c3e50;
-  color: white;
-  padding: 1rem 0;
-  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
+/* Layout */
+.app-main {
+  min-height: 100vh;
+  transition: margin-left var(--transition-normal);
 }
 
-.container {
+.app-main.with-sidebar {
+  margin-left: var(--sidebar-width);
+}
+
+.app-main.with-sidebar.sidebar-collapsed {
+  margin-left: var(--sidebar-collapsed-width);
+}
+
+.content {
   max-width: 1200px;
   margin: 0 auto;
-  padding: 0 1rem;
-  display: flex;
-  justify-content: space-between;
+  padding: 2rem 1.5rem;
+}
+
+/* Mobile header */
+.mobile-header {
+  display: none;
+  position: sticky;
+  top: 0;
+  z-index: 50;
   align-items: center;
+  gap: 0.75rem;
+  padding: 0.75rem 1rem;
+  background: var(--color-surface);
+  border-bottom: 1px solid var(--color-border);
+  box-shadow: var(--shadow-sm);
 }
 
-h1 {
-  margin: 0;
-  font-size: 1.5rem;
-}
-
-nav {
-  display: flex;
-  gap: 1.5rem;
-  align-items: center;
-}
-
-nav a {
-  color: white;
-  text-decoration: none;
-  padding: 0.5rem 1rem;
-  border-radius: 4px;
-  transition: background 0.2s;
-}
-
-nav a:hover,
-nav a.router-link-active {
-  background: rgba(255,255,255,0.1);
-}
-
-.btn-logout {
-  background: #e74c3c;
-  color: white;
+.mobile-hamburger {
+  background: transparent;
   border: none;
-  padding: 0.5rem 1rem;
-  border-radius: 4px;
+  color: var(--color-text-primary);
   cursor: pointer;
-  font-size: 0.9rem;
+  padding: 0.4rem;
+  border-radius: var(--radius-sm);
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  transition: background var(--transition-fast);
 }
 
-.btn-logout:hover {
-  background: #c0392b;
+.mobile-hamburger:hover {
+  background: var(--color-bg-secondary);
 }
 
-.main {
-  max-width: 1200px;
-  margin: 2rem auto;
-  padding: 0 1rem;
+.mobile-title {
+  font-size: 1.1rem;
+  font-weight: 700;
+  color: var(--color-text-primary);
+  flex: 1;
+}
+
+.mobile-actions {
+  display: flex;
+  align-items: center;
+  gap: 0.25rem;
 }
 
 /* Notifications */
@@ -246,44 +234,47 @@ nav a.router-link-active {
 .notification-bell {
   background: transparent;
   border: none;
-  color: white;
+  color: var(--color-text-secondary);
   cursor: pointer;
-  padding: 0.5rem;
-  border-radius: 4px;
+  padding: 0.4rem;
+  border-radius: var(--radius-sm);
   position: relative;
   display: flex;
   align-items: center;
   justify-content: center;
-  transition: background 0.2s;
+  transition: all var(--transition-fast);
 }
 
 .notification-bell:hover {
-  background: rgba(255, 255, 255, 0.1);
+  background: var(--color-bg-secondary);
+  color: var(--color-text-primary);
 }
 
-.notification-bell .badge {
+.notification-badge {
   position: absolute;
-  top: 2px;
-  right: 2px;
-  background: #e74c3c;
+  top: 0;
+  right: 0;
+  background: var(--color-danger);
   color: white;
   border-radius: 10px;
-  padding: 2px 6px;
-  font-size: 0.7rem;
+  padding: 1px 5px;
+  font-size: 0.65rem;
   font-weight: bold;
-  min-width: 18px;
+  min-width: 16px;
   text-align: center;
+  line-height: 1.3;
 }
 
 .notification-dropdown {
   position: absolute;
-  top: calc(100% + 10px);
+  top: calc(100% + 8px);
   right: 0;
-  background: white;
-  border-radius: 8px;
-  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
+  background: var(--color-surface);
+  border-radius: var(--radius-lg);
+  box-shadow: var(--shadow-lg);
+  border: 1px solid var(--color-border);
   width: 360px;
-  max-height: 400px;
+  max-height: 420px;
   overflow: hidden;
   z-index: 1000;
   display: flex;
@@ -294,42 +285,39 @@ nav a.router-link-active {
   display: flex;
   justify-content: space-between;
   align-items: center;
-  padding: 1rem;
-  border-bottom: 1px solid #e0e0e0;
-  background: #f8f9fa;
+  padding: 1rem 1.25rem;
+  border-bottom: 1px solid var(--color-border-light);
 }
 
 .notification-header h3 {
   margin: 0;
   font-size: 1rem;
-  color: #2c3e50;
+  color: var(--color-text-primary);
 }
 
 .close-btn {
   background: none;
   border: none;
-  font-size: 1.5rem;
-  color: #7f8c8d;
+  color: var(--color-text-muted);
   cursor: pointer;
-  padding: 0;
-  width: 24px;
-  height: 24px;
+  padding: 0.25rem;
   display: flex;
   align-items: center;
   justify-content: center;
-  border-radius: 4px;
+  border-radius: var(--radius-sm);
+  transition: all var(--transition-fast);
 }
 
 .close-btn:hover {
-  background: #e0e0e0;
-  color: #2c3e50;
+  background: var(--color-bg-secondary);
+  color: var(--color-text-primary);
 }
 
 .notification-loading,
 .notification-empty {
   padding: 2rem;
   text-align: center;
-  color: #7f8c8d;
+  color: var(--color-text-muted);
 }
 
 .notification-list {
@@ -338,28 +326,32 @@ nav a.router-link-active {
 }
 
 .notification-item {
-  padding: 1rem;
-  border-bottom: 1px solid #e0e0e0;
+  padding: 1rem 1.25rem;
+  border-bottom: 1px solid var(--color-border-light);
   cursor: pointer;
-  transition: background 0.2s;
+  transition: background var(--transition-fast);
 }
 
 .notification-item:hover {
-  background: #f8f9fa;
+  background: var(--color-surface-hover);
+}
+
+.notification-item:last-child {
+  border-bottom: none;
 }
 
 .notification-item.unread {
-  background: #e8f4fd;
-  border-left: 3px solid #3498db;
+  background: var(--color-accent-light);
+  border-left: 3px solid var(--color-accent);
 }
 
 .notification-item.unread:hover {
-  background: #d6ebfa;
+  background: var(--color-surface-hover);
 }
 
 .notification-title {
   font-weight: 600;
-  color: #2c3e50;
+  color: var(--color-text-primary);
   margin-bottom: 0.25rem;
   font-size: 0.9rem;
 }
@@ -369,21 +361,41 @@ nav a.router-link-active {
 }
 
 .notification-message {
-  color: #555;
+  color: var(--color-text-secondary);
   font-size: 0.85rem;
   margin-bottom: 0.5rem;
   line-height: 1.4;
 }
 
 .notification-time {
-  color: #95a5a6;
+  color: var(--color-text-muted);
   font-size: 0.75rem;
 }
 
 /* Responsive */
 @media (max-width: 768px) {
+  .app-main.with-sidebar {
+    margin-left: 0;
+  }
+
+  .app-main.with-sidebar.sidebar-collapsed {
+    margin-left: 0;
+  }
+
+  .mobile-header {
+    display: flex;
+  }
+
+  .content {
+    padding: 1.25rem 1rem;
+  }
+
   .notification-dropdown {
-    width: 320px;
+    position: fixed;
+    left: 1rem;
+    right: 1rem;
+    top: 60px;
+    width: auto;
   }
 }
 </style>
diff --git a/frontend/src/assets/main.css b/frontend/src/assets/main.css
index ad8e30a..40fe954 100644
--- a/frontend/src/assets/main.css
+++ b/frontend/src/assets/main.css
@@ -9,8 +9,8 @@
 body {
   font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
   line-height: 1.6;
-  color: #2c3e50;
-  background: #f5f5f5;
+  color: var(--color-text-primary);
+  background: var(--color-bg-primary);
 }
 
 #app {
@@ -21,37 +21,37 @@ body {
 .btn {
   padding: 0.75rem 1.5rem;
   border: none;
-  border-radius: 4px;
+  border-radius: var(--radius-sm);
   cursor: pointer;
   font-size: 1rem;
-  transition: all 0.2s;
+  transition: all var(--transition-fast);
 }
 
 .btn-primary {
-  background: #3498db;
+  background: var(--color-accent);
   color: white;
 }
 
 .btn-primary:hover {
-  background: #2980b9;
+  background: var(--color-accent-hover);
 }
 
 .btn-success {
-  background: #27ae60;
+  background: var(--color-success);
   color: white;
 }
 
 .btn-success:hover {
-  background: #229954;
+  filter: brightness(0.9);
 }
 
 .btn-danger {
-  background: #e74c3c;
+  background: var(--color-danger);
   color: white;
 }
 
 .btn-danger:hover {
-  background: #c0392b;
+  filter: brightness(0.9);
 }
 
 /* Forms */
@@ -63,6 +63,7 @@ body {
   display: block;
   margin-bottom: 0.5rem;
   font-weight: 500;
+  color: var(--color-text-primary);
 }
 
 .form-group input,
@@ -70,57 +71,61 @@ body {
 .form-group textarea {
   width: 100%;
   padding: 0.75rem;
-  border: 1px solid #ddd;
-  border-radius: 4px;
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-sm);
   font-size: 1rem;
+  background: var(--color-surface);
+  color: var(--color-text-primary);
+  transition: border-color var(--transition-fast);
 }
 
 .form-group input:focus,
 .form-group select:focus,
 .form-group textarea:focus {
   outline: none;
-  border-color: #3498db;
+  border-color: var(--color-accent);
 }
 
 .error {
-  color: #e74c3c;
+  color: var(--color-danger);
   font-size: 0.9rem;
   margin-top: 0.25rem;
 }
 
 /* Cards */
 .card {
-  background: white;
-  border-radius: 8px;
+  background: var(--color-surface);
+  border-radius: var(--radius-md);
   padding: 1.5rem;
-  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
+  box-shadow: var(--shadow-sm);
+  border: 1px solid var(--color-border);
 }
 
 /* Status badges */
 .badge {
   display: inline-block;
   padding: 0.25rem 0.75rem;
-  border-radius: 12px;
+  border-radius: var(--radius-lg);
   font-size: 0.85rem;
   font-weight: 500;
 }
 
 .badge-pending {
-  background: #fff3cd;
-  color: #856404;
+  background: color-mix(in srgb, var(--color-warning) 15%, transparent);
+  color: var(--color-warning);
 }
 
 .badge-approved {
-  background: #d4edda;
-  color: #155724;
+  background: color-mix(in srgb, var(--color-success) 15%, transparent);
+  color: var(--color-success);
 }
 
 .badge-rejected {
-  background: #f8d7da;
-  color: #721c24;
+  background: color-mix(in srgb, var(--color-danger) 15%, transparent);
+  color: var(--color-danger);
 }
 
 .badge-canceled {
-  background: #e2e3e5;
-  color: #383d41;
+  background: var(--color-bg-tertiary);
+  color: var(--color-text-secondary);
 }
diff --git a/frontend/src/assets/theme.css b/frontend/src/assets/theme.css
new file mode 100644
index 0000000..c9b12ff
--- /dev/null
+++ b/frontend/src/assets/theme.css
@@ -0,0 +1,69 @@
+/* Design Tokens - Light Theme (default) */
+:root {
+  /* Base colors */
+  --color-bg-primary: #ffffff;
+  --color-bg-secondary: #f8f9fa;
+  --color-bg-tertiary: #f1f3f5;
+  --color-surface: #ffffff;
+  --color-surface-hover: #f8f9fa;
+
+  /* Text */
+  --color-text-primary: #1a1a2e;
+  --color-text-secondary: #6b7280;
+  --color-text-muted: #9ca3af;
+
+  /* Accent */
+  --color-accent: #6366f1;
+  --color-accent-hover: #4f46e5;
+  --color-accent-light: #eef2ff;
+
+  /* Semantic */
+  --color-success: #10b981;
+  --color-warning: #f59e0b;
+  --color-danger: #ef4444;
+  --color-info: #3b82f6;
+
+  /* Borders */
+  --color-border: #e5e7eb;
+  --color-border-light: #f3f4f6;
+
+  /* Shadows */
+  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
+  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
+  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
+
+  /* Sidebar */
+  --sidebar-width: 260px;
+  --sidebar-collapsed-width: 68px;
+  --sidebar-bg: #1a1a2e;
+  --sidebar-text: #a1a1b5;
+  --sidebar-text-active: #ffffff;
+  --sidebar-hover-bg: rgba(255, 255, 255, 0.08);
+
+  /* Spacing */
+  --radius-sm: 6px;
+  --radius-md: 8px;
+  --radius-lg: 12px;
+
+  /* Transitions */
+  --transition-fast: 150ms ease;
+  --transition-normal: 250ms ease;
+}
+
+/* Dark Theme */
+[data-theme="dark"] {
+  --color-bg-primary: #0f0f1a;
+  --color-bg-secondary: #1a1a2e;
+  --color-bg-tertiary: #232340;
+  --color-surface: #1a1a2e;
+  --color-surface-hover: #232340;
+  --color-text-primary: #e5e5ef;
+  --color-text-secondary: #9ca3af;
+  --color-text-muted: #6b7280;
+  --color-accent-light: #1e1b4b;
+  --color-border: #2d2d4a;
+  --color-border-light: #232340;
+  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.2);
+  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.3);
+  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.4);
+}
diff --git a/frontend/src/components/AppSidebar.vue b/frontend/src/components/AppSidebar.vue
new file mode 100644
index 0000000..5f72d0e
--- /dev/null
+++ b/frontend/src/components/AppSidebar.vue
@@ -0,0 +1,320 @@
+<template>
+  <aside class="sidebar" :class="{ collapsed, 'mobile-open': mobileOpen }">
+    <div class="sidebar-header">
+      <LayoutDashboard :size="24" class="sidebar-logo-icon" />
+      <span v-show="!collapsed" class="sidebar-title">Space Booking</span>
+    </div>
+
+    <nav class="sidebar-nav">
+      <div class="nav-section">
+        <span v-show="!collapsed" class="nav-section-label">Main</span>
+        <router-link
+          v-for="item in mainNav"
+          :key="item.to"
+          :to="item.to"
+          class="nav-link"
+          :class="{ active: isActive(item.to) }"
+          @click="closeMobile"
+        >
+          <component :is="item.icon" :size="20" class="nav-icon" />
+          <span v-show="!collapsed" class="nav-label">{{ item.label }}</span>
+        </router-link>
+      </div>
+
+      <div v-if="authStore.isAdmin" class="nav-section">
+        <span v-show="!collapsed" class="nav-section-label">Admin</span>
+        <router-link
+          v-for="item in adminNav"
+          :key="item.to"
+          :to="item.to"
+          class="nav-link"
+          :class="{ active: isActive(item.to) }"
+          @click="closeMobile"
+        >
+          <component :is="item.icon" :size="20" class="nav-icon" />
+          <span v-show="!collapsed" class="nav-label">{{ item.label }}</span>
+        </router-link>
+      </div>
+    </nav>
+
+    <div class="sidebar-footer">
+      <div v-show="!collapsed" class="user-info">
+        <div class="user-avatar">
+          {{ authStore.user?.email?.charAt(0).toUpperCase() }}
+        </div>
+        <span class="user-email">{{ authStore.user?.email }}</span>
+      </div>
+
+      <div class="footer-actions">
+        <button class="footer-btn" @click="toggleTheme" :title="themeTitle">
+          <Sun v-if="resolvedTheme === 'light'" :size="18" />
+          <Moon v-else-if="resolvedTheme === 'dark'" :size="18" />
+        </button>
+
+        <button class="footer-btn collapse-toggle desktop-only" @click="toggle" :title="collapsed ? 'Expand sidebar' : 'Collapse sidebar'">
+          <ChevronRight v-if="collapsed" :size="18" />
+          <ChevronLeft v-else :size="18" />
+        </button>
+
+        <button class="footer-btn logout-btn" @click="handleLogout" title="Logout">
+          <LogOut :size="18" />
+        </button>
+      </div>
+    </div>
+  </aside>
+
+  <div v-if="mobileOpen" class="sidebar-overlay" @click="closeMobile" />
+</template>
+
+<script setup lang="ts">
+import { computed } from 'vue'
+import { useRoute, useRouter } from 'vue-router'
+import { useAuthStore } from '@/stores/auth'
+import { useSidebar } from '@/composables/useSidebar'
+import { useTheme } from '@/composables/useTheme'
+import {
+  LayoutDashboard,
+  Building2,
+  CalendarDays,
+  User,
+  Settings2,
+  Users,
+  ClipboardCheck,
+  Sliders,
+  BarChart3,
+  ScrollText,
+  Sun,
+  Moon,
+  ChevronLeft,
+  ChevronRight,
+  LogOut
+} from 'lucide-vue-next'
+
+const authStore = useAuthStore()
+const route = useRoute()
+const router = useRouter()
+const { collapsed, mobileOpen, toggle, closeMobile } = useSidebar()
+const { theme, resolvedTheme, toggleTheme } = useTheme()
+
+const themeTitle = computed(() => {
+  if (theme.value === 'light') return 'Switch to dark mode'
+  if (theme.value === 'dark') return 'Switch to auto mode'
+  return 'Switch to light mode'
+})
+
+const mainNav = [
+  { to: '/dashboard', icon: LayoutDashboard, label: 'Dashboard' },
+  { to: '/spaces', icon: Building2, label: 'Spaces' },
+  { to: '/my-bookings', icon: CalendarDays, label: 'My Bookings' },
+  { to: '/profile', icon: User, label: 'Profile' },
+]
+
+const adminNav = [
+  { to: '/admin', icon: Settings2, label: 'Spaces Admin' },
+  { to: '/users', icon: Users, label: 'Users' },
+  { to: '/admin/pending', icon: ClipboardCheck, label: 'Pending' },
+  { to: '/admin/settings', icon: Sliders, label: 'Settings' },
+  { to: '/admin/reports', icon: BarChart3, label: 'Reports' },
+  { to: '/admin/audit-log', icon: ScrollText, label: 'Audit Log' },
+]
+
+const isActive = (path: string) => {
+  if (path === '/dashboard') return route.path === '/dashboard'
+  return route.path.startsWith(path)
+}
+
+const handleLogout = () => {
+  authStore.logout()
+  router.push('/login')
+}
+</script>
+
+<style scoped>
+.sidebar {
+  position: fixed;
+  top: 0;
+  left: 0;
+  bottom: 0;
+  width: var(--sidebar-width);
+  background: var(--sidebar-bg);
+  display: flex;
+  flex-direction: column;
+  z-index: 100;
+  transition: width var(--transition-normal), transform var(--transition-normal);
+  overflow: hidden;
+}
+
+.sidebar.collapsed {
+  width: var(--sidebar-collapsed-width);
+}
+
+/* Header */
+.sidebar-header {
+  display: flex;
+  align-items: center;
+  gap: 0.75rem;
+  padding: 1.25rem 1.25rem 1rem;
+  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
+  min-height: 60px;
+}
+
+.sidebar-logo-icon {
+  color: var(--color-accent);
+  flex-shrink: 0;
+}
+
+.sidebar-title {
+  font-size: 1.1rem;
+  font-weight: 700;
+  color: var(--sidebar-text-active);
+  white-space: nowrap;
+  overflow: hidden;
+}
+
+/* Navigation */
+.sidebar-nav {
+  flex: 1;
+  overflow-y: auto;
+  padding: 0.75rem 0;
+}
+
+.nav-section {
+  margin-bottom: 0.5rem;
+}
+
+.nav-section-label {
+  display: block;
+  padding: 0.5rem 1.25rem 0.25rem;
+  font-size: 0.7rem;
+  font-weight: 600;
+  text-transform: uppercase;
+  letter-spacing: 0.05em;
+  color: var(--sidebar-text);
+  opacity: 0.6;
+}
+
+.nav-link {
+  display: flex;
+  align-items: center;
+  gap: 0.75rem;
+  padding: 0.6rem 1.25rem;
+  color: var(--sidebar-text);
+  text-decoration: none;
+  transition: all var(--transition-fast);
+  border-left: 3px solid transparent;
+  white-space: nowrap;
+}
+
+.nav-link:hover {
+  background: var(--sidebar-hover-bg);
+  color: var(--sidebar-text-active);
+}
+
+.nav-link.active {
+  color: var(--sidebar-text-active);
+  background: var(--sidebar-hover-bg);
+  border-left-color: var(--color-accent);
+}
+
+.nav-icon {
+  flex-shrink: 0;
+}
+
+.nav-label {
+  overflow: hidden;
+  text-overflow: ellipsis;
+}
+
+/* Footer */
+.sidebar-footer {
+  border-top: 1px solid rgba(255, 255, 255, 0.08);
+  padding: 0.75rem 1rem;
+}
+
+.user-info {
+  display: flex;
+  align-items: center;
+  gap: 0.75rem;
+  padding: 0.5rem 0.25rem;
+  margin-bottom: 0.5rem;
+  overflow: hidden;
+}
+
+.user-avatar {
+  width: 32px;
+  height: 32px;
+  border-radius: 50%;
+  background: var(--color-accent);
+  color: white;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  font-size: 0.85rem;
+  font-weight: 600;
+  flex-shrink: 0;
+}
+
+.user-email {
+  font-size: 0.8rem;
+  color: var(--sidebar-text);
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
+.footer-actions {
+  display: flex;
+  align-items: center;
+  gap: 0.25rem;
+}
+
+.footer-btn {
+  background: transparent;
+  border: none;
+  color: var(--sidebar-text);
+  cursor: pointer;
+  padding: 0.5rem;
+  border-radius: var(--radius-sm);
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  transition: all var(--transition-fast);
+}
+
+.footer-btn:hover {
+  background: var(--sidebar-hover-bg);
+  color: var(--sidebar-text-active);
+}
+
+.logout-btn:hover {
+  color: var(--color-danger);
+}
+
+/* Sidebar overlay for mobile */
+.sidebar-overlay {
+  position: fixed;
+  inset: 0;
+  background: rgba(0, 0, 0, 0.5);
+  z-index: 99;
+}
+
+/* Mobile styles */
+@media (max-width: 768px) {
+  .sidebar {
+    transform: translateX(-100%);
+    width: var(--sidebar-width);
+  }
+
+  .sidebar.mobile-open {
+    transform: translateX(0);
+  }
+
+  .sidebar.collapsed {
+    width: var(--sidebar-width);
+  }
+
+  .desktop-only {
+    display: none;
+  }
+}
+</style>
diff --git a/frontend/src/components/AttachmentsList.vue b/frontend/src/components/AttachmentsList.vue
index 4499a54..05f4fc7 100644
--- a/frontend/src/components/AttachmentsList.vue
+++ b/frontend/src/components/AttachmentsList.vue
@@ -126,7 +126,7 @@ onMounted(() => {
 .attachments-title {
   font-size: 16px;
   font-weight: 600;
-  color: #111827;
+  color: var(--color-text-primary);
   margin: 0 0 12px 0;
 }
 
@@ -134,19 +134,19 @@ onMounted(() => {
 .error,
 .no-attachments {
   padding: 12px;
-  border-radius: 6px;
+  border-radius: var(--radius-sm);
   font-size: 14px;
 }
 
 .loading,
 .no-attachments {
-  background: #f3f4f6;
-  color: #6b7280;
+  background: var(--color-bg-tertiary);
+  color: var(--color-text-secondary);
 }
 
 .error {
-  background: #fee2e2;
-  color: #991b1b;
+  background: color-mix(in srgb, var(--color-danger) 10%, transparent);
+  color: var(--color-danger);
 }
 
 .attachment-items {
@@ -160,9 +160,9 @@ onMounted(() => {
   align-items: center;
   justify-content: space-between;
   padding: 12px;
-  background: #f9fafb;
-  border: 1px solid #e5e7eb;
-  border-radius: 6px;
+  background: var(--color-bg-secondary);
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-sm);
   margin-bottom: 8px;
   gap: 12px;
 }
@@ -189,7 +189,7 @@ onMounted(() => {
 
 .attachment-name {
   font-size: 14px;
-  color: #3b82f6;
+  color: var(--color-accent);
   text-decoration: none;
   font-weight: 500;
   overflow: hidden;
@@ -203,23 +203,23 @@ onMounted(() => {
 
 .attachment-meta {
   font-size: 12px;
-  color: #6b7280;
+  color: var(--color-text-secondary);
 }
 
 .btn-delete {
   padding: 6px 12px;
-  background: white;
-  color: #ef4444;
-  border: 1px solid #ef4444;
-  border-radius: 4px;
+  background: var(--color-surface);
+  color: var(--color-danger);
+  border: 1px solid var(--color-danger);
+  border-radius: var(--radius-sm);
   font-size: 13px;
   cursor: pointer;
-  transition: all 0.2s;
+  transition: all var(--transition-fast);
   flex-shrink: 0;
 }
 
 .btn-delete:hover:not(:disabled) {
-  background: #fef2f2;
+  background: color-mix(in srgb, var(--color-danger) 5%, transparent);
 }
 
 .btn-delete:disabled {
diff --git a/frontend/src/components/BookingForm.vue b/frontend/src/components/BookingForm.vue
index bae8a1b..9c767f1 100644
--- a/frontend/src/components/BookingForm.vue
+++ b/frontend/src/components/BookingForm.vue
@@ -437,7 +437,7 @@ onMounted(() => {
   display: block;
   margin-bottom: 6px;
   font-weight: 500;
-  color: #374151;
+  color: var(--color-text-primary);
   font-size: 14px;
 }
 
@@ -445,7 +445,7 @@ onMounted(() => {
   display: block;
   margin-bottom: 4px;
   font-weight: 400;
-  color: #6b7280;
+  color: var(--color-text-secondary);
   font-size: 12px;
 }
 
@@ -464,26 +464,28 @@ onMounted(() => {
 .form-textarea {
   width: 100%;
   padding: 8px 12px;
-  border: 1px solid #d1d5db;
-  border-radius: 4px;
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-sm);
   font-size: 14px;
   font-family: inherit;
-  transition: border-color 0.2s;
+  transition: border-color var(--transition-fast);
+  background: var(--color-surface);
+  color: var(--color-text-primary);
 }
 
 .form-input:focus,
 .form-textarea:focus {
   outline: none;
-  border-color: #3b82f6;
-  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
+  border-color: var(--color-accent);
+  box-shadow: 0 0 0 3px color-mix(in srgb, var(--color-accent) 15%, transparent);
 }
 
 .form-input-error {
-  border-color: #ef4444;
+  border-color: var(--color-danger);
 }
 
 .form-input:disabled {
-  background-color: #f3f4f6;
+  background-color: var(--color-bg-tertiary);
   cursor: not-allowed;
 }
 
@@ -494,24 +496,24 @@ onMounted(() => {
 .form-error {
   display: block;
   margin-top: 4px;
-  color: #ef4444;
+  color: var(--color-danger);
   font-size: 13px;
 }
 
 .api-error {
   padding: 12px;
-  background: #fee2e2;
-  color: #991b1b;
-  border-radius: 4px;
+  background: color-mix(in srgb, var(--color-danger) 10%, transparent);
+  color: var(--color-danger);
+  border-radius: var(--radius-sm);
   margin-bottom: 16px;
   font-size: 14px;
 }
 
 .success-message {
   padding: 12px;
-  background: #d1fae5;
-  color: #065f46;
-  border-radius: 4px;
+  background: color-mix(in srgb, var(--color-success) 10%, transparent);
+  color: var(--color-success);
+  border-radius: var(--radius-sm);
   margin-bottom: 16px;
   font-size: 14px;
 }
@@ -525,11 +527,11 @@ onMounted(() => {
 .btn {
   padding: 10px 20px;
   border: none;
-  border-radius: 4px;
+  border-radius: var(--radius-sm);
   font-size: 14px;
   font-weight: 500;
   cursor: pointer;
-  transition: all 0.2s;
+  transition: all var(--transition-fast);
 }
 
 .btn:disabled {
@@ -538,33 +540,34 @@ onMounted(() => {
 }
 
 .btn-primary {
-  background: #3b82f6;
+  background: var(--color-accent);
   color: white;
 }
 
 .btn-primary:hover:not(:disabled) {
-  background: #2563eb;
+  background: var(--color-accent-hover);
 }
 
 .btn-secondary {
-  background: #6b7280;
+  background: var(--color-text-secondary);
   color: white;
 }
 
 .btn-secondary:hover:not(:disabled) {
-  background: #4b5563;
+  background: var(--color-text-primary);
 }
 
 .warning-banner {
-  background: #fff3cd;
-  border: 1px solid #ffc107;
-  border-radius: 4px;
+  background: color-mix(in srgb, var(--color-warning) 15%, transparent);
+  border: 1px solid var(--color-warning);
+  border-radius: var(--radius-sm);
   padding: 12px;
   margin-bottom: 16px;
   display: flex;
   gap: 12px;
   align-items: flex-start;
   font-size: 14px;
+  color: var(--color-text-primary);
 }
 
 .warning-icon {
diff --git a/frontend/src/components/CollapsibleSection.vue b/frontend/src/components/CollapsibleSection.vue
new file mode 100644
index 0000000..9cb01b4
--- /dev/null
+++ b/frontend/src/components/CollapsibleSection.vue
@@ -0,0 +1,94 @@
+<template>
+  <div class="collapsible-section">
+    <div class="section-header" @click="toggle" role="button" :aria-expanded="isOpen">
+      <component :is="icon" v-if="icon" :size="20" class="section-icon" />
+      <h3 class="section-title">{{ title }}</h3>
+      <div class="header-actions" @click.stop>
+        <slot name="header-actions" />
+      </div>
+      <ChevronDown class="chevron" :class="{ rotated: !isOpen }" :size="18" />
+    </div>
+    <div v-show="isOpen" class="section-content">
+      <slot />
+    </div>
+  </div>
+</template>
+
+<script setup lang="ts">
+import { ref, type Component } from 'vue'
+import { ChevronDown } from 'lucide-vue-next'
+
+const props = withDefaults(defineProps<{
+  title: string
+  icon?: Component
+  defaultOpen?: boolean
+}>(), {
+  defaultOpen: true
+})
+
+const isOpen = ref(props.defaultOpen)
+
+const toggle = () => {
+  isOpen.value = !isOpen.value
+}
+
+defineExpose({ isOpen, toggle })
+</script>
+
+<style scoped>
+.collapsible-section {
+  background: var(--color-surface);
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-lg);
+  box-shadow: var(--shadow-sm);
+  overflow: hidden;
+}
+
+.section-header {
+  display: flex;
+  align-items: center;
+  gap: 0.75rem;
+  padding: 1rem 1.25rem;
+  cursor: pointer;
+  user-select: none;
+  transition: background var(--transition-fast);
+}
+
+.section-header:hover {
+  background: var(--color-surface-hover);
+}
+
+.section-icon {
+  color: var(--color-accent);
+  flex-shrink: 0;
+}
+
+.section-title {
+  margin: 0;
+  font-size: 1rem;
+  font-weight: 600;
+  color: var(--color-text-primary);
+  flex: 1;
+}
+
+.header-actions {
+  display: flex;
+  align-items: center;
+  gap: 0.5rem;
+}
+
+.chevron {
+  color: var(--color-text-muted);
+  transition: transform var(--transition-normal);
+  flex-shrink: 0;
+}
+
+.chevron.rotated {
+  transform: rotate(-90deg);
+}
+
+.section-content {
+  padding: 1.25rem;
+  border-top: 1px solid var(--color-border-light);
+}
+</style>
diff --git a/frontend/src/components/SpaceCalendar.vue b/frontend/src/components/SpaceCalendar.vue
index 7bd4731..9148bcf 100644
--- a/frontend/src/components/SpaceCalendar.vue
+++ b/frontend/src/components/SpaceCalendar.vue
@@ -313,32 +313,32 @@ defineExpose({ refresh })
 
 <style scoped>
 .space-calendar {
-  background: white;
-  border-radius: 8px;
+  background: var(--color-surface);
+  border-radius: var(--radius-md);
   padding: 24px;
-  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
+  box-shadow: var(--shadow-sm);
 }
 
 .admin-notice {
-  background: #e3f2fd;
+  background: color-mix(in srgb, var(--color-info) 15%, transparent);
   padding: 8px 16px;
   margin-bottom: 16px;
-  border-radius: 4px;
-  color: #1976d2;
+  border-radius: var(--radius-sm);
+  color: var(--color-info);
   font-size: 14px;
 }
 
 .error {
   padding: 12px;
-  background: #fee2e2;
-  color: #991b1b;
-  border-radius: 4px;
+  background: color-mix(in srgb, var(--color-danger) 10%, transparent);
+  color: var(--color-danger);
+  border-radius: var(--radius-sm);
   margin-bottom: 16px;
 }
 
 .loading {
   text-align: center;
-  color: #6b7280;
+  color: var(--color-text-secondary);
   padding: 24px;
 }
 
@@ -357,23 +357,23 @@ defineExpose({ refresh })
 }
 
 .modal-content {
-  background: white;
+  background: var(--color-surface);
   padding: 24px;
-  border-radius: 8px;
+  border-radius: var(--radius-md);
   max-width: 500px;
   width: 90%;
-  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
+  box-shadow: var(--shadow-lg);
 }
 
 .modal-content h3 {
   margin-top: 0;
   margin-bottom: 16px;
-  color: #1f2937;
+  color: var(--color-text-primary);
 }
 
 .modal-content p {
   margin-bottom: 20px;
-  color: #6b7280;
+  color: var(--color-text-secondary);
 }
 
 .time-comparison {
@@ -382,26 +382,27 @@ defineExpose({ refresh })
   gap: 16px;
   margin: 20px 0;
   padding: 16px;
-  background: #f9fafb;
-  border-radius: 4px;
+  background: var(--color-bg-secondary);
+  border-radius: var(--radius-sm);
 }
 
 .old-time,
 .new-time {
   flex: 1;
   font-size: 14px;
+  color: var(--color-text-secondary);
 }
 
 .old-time strong,
 .new-time strong {
-  color: #374151;
+  color: var(--color-text-primary);
   display: block;
   margin-bottom: 4px;
 }
 
 .arrow {
   font-size: 24px;
-  color: #9ca3af;
+  color: var(--color-text-muted);
 }
 
 .modal-actions {
@@ -412,40 +413,40 @@ defineExpose({ refresh })
 }
 
 .btn-primary {
-  background: #3b82f6;
+  background: var(--color-accent);
   color: white;
   border: none;
   padding: 10px 20px;
-  border-radius: 4px;
+  border-radius: var(--radius-sm);
   cursor: pointer;
   font-size: 14px;
   font-weight: 500;
-  transition: background 0.2s;
+  transition: background var(--transition-fast);
 }
 
 .btn-primary:hover:not(:disabled) {
-  background: #2563eb;
+  background: var(--color-accent-hover);
 }
 
 .btn-primary:disabled {
-  background: #93c5fd;
+  opacity: 0.6;
   cursor: not-allowed;
 }
 
 .btn-secondary {
-  background: #f3f4f6;
-  color: #374151;
-  border: 1px solid #d1d5db;
+  background: var(--color-bg-tertiary);
+  color: var(--color-text-primary);
+  border: 1px solid var(--color-border);
   padding: 10px 20px;
-  border-radius: 4px;
+  border-radius: var(--radius-sm);
   cursor: pointer;
   font-size: 14px;
   font-weight: 500;
-  transition: background 0.2s;
+  transition: background var(--transition-fast);
 }
 
 .btn-secondary:hover:not(:disabled) {
-  background: #e5e7eb;
+  background: var(--color-border);
 }
 
 .btn-secondary:disabled {
@@ -459,28 +460,28 @@ defineExpose({ refresh })
 }
 
 :deep(.fc-button) {
-  background: #3b82f6;
-  border-color: #3b82f6;
+  background: var(--color-accent);
+  border-color: var(--color-accent);
   text-transform: capitalize;
 }
 
 :deep(.fc-button:hover) {
-  background: #2563eb;
-  border-color: #2563eb;
+  background: var(--color-accent-hover);
+  border-color: var(--color-accent-hover);
 }
 
 :deep(.fc-button-active) {
-  background: #1d4ed8 !important;
-  border-color: #1d4ed8 !important;
+  background: var(--color-accent-hover) !important;
+  border-color: var(--color-accent-hover) !important;
 }
 
 :deep(.fc-daygrid-day-number) {
-  color: #374151;
+  color: var(--color-text-primary);
   font-weight: 500;
 }
 
 :deep(.fc-col-header-cell-cushion) {
-  color: #374151;
+  color: var(--color-text-primary);
   font-weight: 600;
 }
 
diff --git a/frontend/src/composables/useSidebar.ts b/frontend/src/composables/useSidebar.ts
new file mode 100644
index 0000000..c2b7332
--- /dev/null
+++ b/frontend/src/composables/useSidebar.ts
@@ -0,0 +1,43 @@
+import { ref, watch } from 'vue'
+import { useRouter } from 'vue-router'
+
+const STORAGE_KEY = 'space-booking-sidebar-collapsed'
+
+const collapsed = ref(localStorage.getItem(STORAGE_KEY) === 'true')
+const mobileOpen = ref(false)
+
+export function useSidebar() {
+  const router = useRouter()
+
+  // Close mobile sidebar on route change
+  watch(() => router.currentRoute.value.path, () => {
+    mobileOpen.value = false
+  })
+
+  function toggle() {
+    collapsed.value = !collapsed.value
+    localStorage.setItem(STORAGE_KEY, String(collapsed.value))
+  }
+
+  function close() {
+    collapsed.value = true
+    localStorage.setItem(STORAGE_KEY, 'true')
+  }
+
+  function toggleMobile() {
+    mobileOpen.value = !mobileOpen.value
+  }
+
+  function closeMobile() {
+    mobileOpen.value = false
+  }
+
+  return {
+    collapsed,
+    mobileOpen,
+    toggle,
+    close,
+    toggleMobile,
+    closeMobile
+  }
+}
diff --git a/frontend/src/composables/useTheme.ts b/frontend/src/composables/useTheme.ts
new file mode 100644
index 0000000..6eb78a6
--- /dev/null
+++ b/frontend/src/composables/useTheme.ts
@@ -0,0 +1,52 @@
+import { ref, computed, watch, onMounted } from 'vue'
+
+type Theme = 'light' | 'dark' | 'auto'
+
+const STORAGE_KEY = 'space-booking-theme'
+
+const theme = ref<Theme>((localStorage.getItem(STORAGE_KEY) as Theme) || 'light')
+const systemDark = ref(window.matchMedia('(prefers-color-scheme: dark)').matches)
+
+// Listen for system theme changes
+const mediaQuery = window.matchMedia('(prefers-color-scheme: dark)')
+mediaQuery.addEventListener('change', (e) => {
+  systemDark.value = e.matches
+})
+
+const resolvedTheme = computed<'light' | 'dark'>(() => {
+  if (theme.value === 'auto') {
+    return systemDark.value ? 'dark' : 'light'
+  }
+  return theme.value
+})
+
+function applyTheme() {
+  document.documentElement.setAttribute('data-theme', resolvedTheme.value)
+}
+
+watch(resolvedTheme, applyTheme)
+
+export function useTheme() {
+  onMounted(() => {
+    applyTheme()
+  })
+
+  function toggleTheme() {
+    const cycle: Theme[] = ['light', 'dark', 'auto']
+    const idx = cycle.indexOf(theme.value)
+    theme.value = cycle[(idx + 1) % cycle.length]
+    localStorage.setItem(STORAGE_KEY, theme.value)
+  }
+
+  function setTheme(value: Theme) {
+    theme.value = value
+    localStorage.setItem(STORAGE_KEY, value)
+  }
+
+  return {
+    theme,
+    resolvedTheme,
+    toggleTheme,
+    setTheme
+  }
+}
diff --git a/frontend/src/main.ts b/frontend/src/main.ts
index b257fe5..5f1f5cd 100644
--- a/frontend/src/main.ts
+++ b/frontend/src/main.ts
@@ -2,6 +2,7 @@ import { createApp } from 'vue'
 import { createPinia } from 'pinia'
 import App from './App.vue'
 import router from './router'
+import './assets/theme.css'
 import './assets/main.css'
 
 const app = createApp(App)
diff --git a/frontend/src/views/Admin.vue b/frontend/src/views/Admin.vue
index 2669fe3..ee2e325 100644
--- a/frontend/src/views/Admin.vue
+++ b/frontend/src/views/Admin.vue
@@ -3,57 +3,59 @@
     <div class="page-header">
       <h2>Admin Dashboard - Space Management</h2>
       <button class="btn btn-primary" @click="openCreateModal">
+        <Plus :size="16" />
         Create New Space
       </button>
     </div>
 
     <!-- Spaces List -->
-    <div class="card">
-      <h3>All Spaces</h3>
+    <CollapsibleSection title="All Spaces" :icon="Building2">
       <div v-if="loadingSpaces" class="loading">Loading spaces...</div>
       <div v-else-if="spaces.length === 0" class="empty">
         No spaces created yet. Create one above!
       </div>
-      <table v-else class="spaces-table">
-        <thead>
-          <tr>
-            <th>Name</th>
-            <th>Type</th>
-            <th>Capacity</th>
-            <th>Status</th>
-            <th>Actions</th>
-          </tr>
-        </thead>
-        <tbody>
-          <tr v-for="space in spaces" :key="space.id">
-            <td>{{ space.name }}</td>
-            <td>{{ space.type === 'sala' ? 'Sala' : 'Birou' }}</td>
-            <td>{{ space.capacity }}</td>
-            <td>
-              <span :class="['badge', space.is_active ? 'badge-active' : 'badge-inactive']">
-                {{ space.is_active ? 'Active' : 'Inactive' }}
-              </span>
-            </td>
-            <td class="actions">
-              <button
-                class="btn btn-sm btn-secondary"
-                @click="startEdit(space)"
-                :disabled="loading"
-              >
-                Edit
-              </button>
-              <button
-                :class="['btn', 'btn-sm', space.is_active ? 'btn-warning' : 'btn-success']"
-                @click="toggleStatus(space)"
-                :disabled="loading"
-              >
-                {{ space.is_active ? 'Deactivate' : 'Activate' }}
-              </button>
-            </td>
-          </tr>
-        </tbody>
-      </table>
-    </div>
+      <div v-else class="table-responsive">
+        <table class="data-table">
+          <thead>
+            <tr>
+              <th>Name</th>
+              <th>Type</th>
+              <th>Capacity</th>
+              <th>Status</th>
+              <th>Actions</th>
+            </tr>
+          </thead>
+          <tbody>
+            <tr v-for="space in spaces" :key="space.id">
+              <td>{{ space.name }}</td>
+              <td>{{ space.type === 'sala' ? 'Sala' : 'Birou' }}</td>
+              <td>{{ space.capacity }}</td>
+              <td>
+                <span :class="['badge', space.is_active ? 'badge-active' : 'badge-inactive']">
+                  {{ space.is_active ? 'Active' : 'Inactive' }}
+                </span>
+              </td>
+              <td class="actions">
+                <button
+                  class="btn btn-sm btn-secondary"
+                  @click="startEdit(space)"
+                  :disabled="loading"
+                >
+                  Edit
+                </button>
+                <button
+                  :class="['btn', 'btn-sm', space.is_active ? 'btn-warning' : 'btn-success']"
+                  @click="toggleStatus(space)"
+                  :disabled="loading"
+                >
+                  {{ space.is_active ? 'Deactivate' : 'Activate' }}
+                </button>
+              </td>
+            </tr>
+          </tbody>
+        </table>
+      </div>
+    </CollapsibleSection>
 
     <!-- Create/Edit Space Modal -->
     <div v-if="showModal" class="modal" @click.self="closeModal">
@@ -179,6 +181,8 @@
 <script setup lang="ts">
 import { ref, onMounted } from 'vue'
 import { spacesApi, handleApiError } from '@/services/api'
+import CollapsibleSection from '@/components/CollapsibleSection.vue'
+import { Building2, Plus } from 'lucide-vue-next'
 import type { Space } from '@/types'
 
 const spaces = ref<Space[]>([])
@@ -305,17 +309,18 @@ onMounted(() => {
 </script>
 
 <style scoped>
-.admin {
-  max-width: 1200px;
-  margin: 0 auto;
+.page-header {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  margin-bottom: 24px;
+  flex-wrap: wrap;
+  gap: 16px;
 }
 
-.card {
-  background: white;
-  border-radius: 8px;
-  padding: 24px;
-  margin-bottom: 24px;
-  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
+.page-header h2 {
+  margin: 0;
+  color: var(--color-text-primary);
 }
 
 .space-form {
@@ -328,20 +333,20 @@ onMounted(() => {
   margin-top: 16px;
   margin-bottom: 8px;
   padding-top: 16px;
-  border-top: 1px solid #e5e7eb;
+  border-top: 1px solid var(--color-border);
 }
 
 .form-section-header h4 {
   margin: 0 0 4px 0;
   font-size: 16px;
   font-weight: 600;
-  color: #1f2937;
+  color: var(--color-text-primary);
 }
 
 .help-text {
   margin: 0;
   font-size: 13px;
-  color: #6b7280;
+  color: var(--color-text-secondary);
 }
 
 .form-row {
@@ -364,7 +369,7 @@ onMounted(() => {
 
 .form-group label {
   font-weight: 500;
-  color: #374151;
+  color: var(--color-text-primary);
   font-size: 14px;
 }
 
@@ -372,17 +377,19 @@ onMounted(() => {
 .form-group select,
 .form-group textarea {
   padding: 8px 12px;
-  border: 1px solid #d1d5db;
-  border-radius: 4px;
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-sm);
   font-size: 14px;
+  background: var(--color-surface);
+  color: var(--color-text-primary);
 }
 
 .form-group input:focus,
 .form-group select:focus,
 .form-group textarea:focus {
   outline: none;
-  border-color: #3b82f6;
-  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
+  border-color: var(--color-accent);
+  box-shadow: 0 0 0 3px color-mix(in srgb, var(--color-accent) 15%, transparent);
 }
 
 .form-actions {
@@ -392,13 +399,16 @@ onMounted(() => {
 }
 
 .btn {
+  display: inline-flex;
+  align-items: center;
+  gap: 6px;
   padding: 10px 20px;
   border: none;
-  border-radius: 4px;
+  border-radius: var(--radius-sm);
   font-size: 14px;
   font-weight: 500;
   cursor: pointer;
-  transition: all 0.2s;
+  transition: all var(--transition-fast);
 }
 
 .btn:disabled {
@@ -407,39 +417,39 @@ onMounted(() => {
 }
 
 .btn-primary {
-  background: #3b82f6;
+  background: var(--color-accent);
   color: white;
 }
 
 .btn-primary:hover:not(:disabled) {
-  background: #2563eb;
+  background: var(--color-accent-hover);
 }
 
 .btn-secondary {
-  background: #6b7280;
-  color: white;
+  background: var(--color-bg-tertiary);
+  color: var(--color-text-primary);
 }
 
 .btn-secondary:hover:not(:disabled) {
-  background: #4b5563;
+  background: var(--color-border);
 }
 
 .btn-success {
-  background: #10b981;
+  background: var(--color-success);
   color: white;
 }
 
 .btn-success:hover:not(:disabled) {
-  background: #059669;
+  background: color-mix(in srgb, var(--color-success) 85%, black);
 }
 
 .btn-warning {
-  background: #f59e0b;
+  background: var(--color-warning);
   color: white;
 }
 
 .btn-warning:hover:not(:disabled) {
-  background: #d97706;
+  background: color-mix(in srgb, var(--color-warning) 85%, black);
 }
 
 .btn-sm {
@@ -449,53 +459,58 @@ onMounted(() => {
 
 .error {
   padding: 12px;
-  background: #fee2e2;
-  color: #991b1b;
-  border-radius: 4px;
+  background: color-mix(in srgb, var(--color-danger) 10%, transparent);
+  color: var(--color-danger);
+  border-radius: var(--radius-sm);
   margin-top: 12px;
 }
 
 .success {
   padding: 12px;
-  background: #d1fae5;
-  color: #065f46;
-  border-radius: 4px;
+  background: color-mix(in srgb, var(--color-success) 10%, transparent);
+  color: var(--color-success);
+  border-radius: var(--radius-sm);
   margin-top: 12px;
 }
 
 .loading {
   text-align: center;
-  color: #6b7280;
+  color: var(--color-text-secondary);
   padding: 24px;
 }
 
 .empty {
   text-align: center;
-  color: #9ca3af;
+  color: var(--color-text-muted);
   padding: 24px;
 }
 
-.spaces-table {
+.table-responsive {
+  overflow-x: auto;
+}
+
+.data-table {
   width: 100%;
   border-collapse: collapse;
 }
 
-.spaces-table th {
+.data-table th {
   text-align: left;
   padding: 12px;
-  background: #f9fafb;
+  background: var(--color-bg-secondary);
   font-weight: 600;
-  color: #374151;
-  border-bottom: 2px solid #e5e7eb;
+  color: var(--color-text-primary);
+  border-bottom: 2px solid var(--color-border);
 }
 
-.spaces-table td {
+.data-table td {
   padding: 12px;
-  border-bottom: 1px solid #e5e7eb;
+  border-bottom: 1px solid var(--color-border);
+  color: var(--color-text-primary);
 }
 
-.spaces-table tr:hover {
-  background: #f9fafb;
+.data-table tr:hover {
+  background: var(--color-surface-hover);
 }
 
 .badge {
@@ -507,13 +522,13 @@ onMounted(() => {
 }
 
 .badge-active {
-  background: #d1fae5;
-  color: #065f46;
+  background: color-mix(in srgb, var(--color-success) 15%, transparent);
+  color: var(--color-success);
 }
 
 .badge-inactive {
-  background: #fee2e2;
-  color: #991b1b;
+  background: color-mix(in srgb, var(--color-danger) 15%, transparent);
+  color: var(--color-danger);
 }
 
 .actions {
@@ -521,19 +536,6 @@ onMounted(() => {
   gap: 8px;
 }
 
-.page-header {
-  display: flex;
-  justify-content: space-between;
-  align-items: center;
-  margin-bottom: 24px;
-  flex-wrap: wrap;
-  gap: 16px;
-}
-
-.page-header h2 {
-  margin: 0;
-}
-
 .modal {
   position: fixed;
   top: 0;
@@ -548,18 +550,30 @@ onMounted(() => {
 }
 
 .modal-content {
-  background: white;
-  border-radius: 8px;
+  background: var(--color-surface);
+  border-radius: var(--radius-md);
   padding: 24px;
   max-width: 600px;
   width: 90%;
   max-height: 90vh;
   overflow-y: auto;
-  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
+  box-shadow: var(--shadow-lg);
 }
 
 .modal-content h3 {
   margin-top: 0;
   margin-bottom: 20px;
+  color: var(--color-text-primary);
+}
+
+@media (max-width: 768px) {
+  .page-header {
+    flex-direction: column;
+    align-items: stretch;
+  }
+
+  .actions {
+    flex-direction: column;
+  }
 }
 </style>
diff --git a/frontend/src/views/AdminPending.vue b/frontend/src/views/AdminPending.vue
index b20bc48..21b5101 100644
--- a/frontend/src/views/AdminPending.vue
+++ b/frontend/src/views/AdminPending.vue
@@ -3,8 +3,7 @@
     <h2>Admin Dashboard - Pending Booking Requests</h2>
 
     <!-- Filters Card -->
-    <div class="card">
-      <h3>Filters</h3>
+    <CollapsibleSection title="Filters" :icon="Filter">
       <div class="filters">
         <div class="form-group">
           <label for="filter-space">Filter by Space</label>
@@ -16,7 +15,7 @@
           </select>
         </div>
       </div>
-    </div>
+    </CollapsibleSection>
 
     <!-- Loading State -->
     <div v-if="loading" class="card">
@@ -32,65 +31,66 @@
     </div>
 
     <!-- Bookings Table -->
-    <div v-else class="card">
-      <h3>Pending Requests ({{ bookings.length }})</h3>
-      <table class="bookings-table">
-        <thead>
-          <tr>
-            <th>User</th>
-            <th>Space</th>
-            <th>Date</th>
-            <th>Time</th>
-            <th>Title</th>
-            <th>Description</th>
-            <th>Actions</th>
-          </tr>
-        </thead>
-        <tbody>
-          <tr v-for="booking in bookings" :key="booking.id">
-            <td>
-              <div class="user-info">
-                <div class="user-name">{{ booking.user?.full_name || 'Unknown' }}</div>
-                <div class="user-email">{{ booking.user?.email || '-' }}</div>
-                <div class="user-org" v-if="booking.user?.organization">
-                  {{ booking.user.organization }}
+    <CollapsibleSection v-else :title="`Pending Requests (${bookings.length})`" :icon="ClipboardCheck">
+      <div class="table-responsive">
+        <table class="data-table">
+          <thead>
+            <tr>
+              <th>User</th>
+              <th>Space</th>
+              <th>Date</th>
+              <th>Time</th>
+              <th>Title</th>
+              <th>Description</th>
+              <th>Actions</th>
+            </tr>
+          </thead>
+          <tbody>
+            <tr v-for="booking in bookings" :key="booking.id">
+              <td>
+                <div class="user-info">
+                  <div class="user-name">{{ booking.user?.full_name || 'Unknown' }}</div>
+                  <div class="user-email">{{ booking.user?.email || '-' }}</div>
+                  <div class="user-org" v-if="booking.user?.organization">
+                    {{ booking.user.organization }}
+                  </div>
                 </div>
-              </div>
-            </td>
-            <td>
-              <div class="space-info">
-                <div class="space-name">{{ booking.space?.name || 'Unknown Space' }}</div>
-                <div class="space-type">{{ formatType(booking.space?.type || '') }}</div>
-              </div>
-            </td>
-            <td>{{ formatDate(booking.start_datetime) }}</td>
-            <td>{{ formatTime(booking.start_datetime, booking.end_datetime) }}</td>
-            <td>{{ booking.title }}</td>
-            <td>
-              <div class="description" :title="booking.description || '-'">
-                {{ truncateText(booking.description || '-', 40) }}
-              </div>
-            </td>
-            <td class="actions">
-              <button
-                class="btn btn-sm btn-success"
-                @click="handleApprove(booking)"
-                :disabled="processing === booking.id"
-              >
-                {{ processing === booking.id ? 'Processing...' : 'Approve' }}
-              </button>
-              <button
-                class="btn btn-sm btn-danger"
-                @click="showRejectModal(booking)"
-                :disabled="processing === booking.id"
-              >
-                Reject
-              </button>
-            </td>
-          </tr>
-        </tbody>
-      </table>
-    </div>
+              </td>
+              <td>
+                <div class="space-info">
+                  <div class="space-name">{{ booking.space?.name || 'Unknown Space' }}</div>
+                  <div class="space-type">{{ formatType(booking.space?.type || '') }}</div>
+                </div>
+              </td>
+              <td>{{ formatDate(booking.start_datetime) }}</td>
+              <td>{{ formatTime(booking.start_datetime, booking.end_datetime) }}</td>
+              <td>{{ booking.title }}</td>
+              <td>
+                <div class="description" :title="booking.description || '-'">
+                  {{ truncateText(booking.description || '-', 40) }}
+                </div>
+              </td>
+              <td class="actions">
+                <button
+                  class="btn btn-sm btn-success"
+                  @click="handleApprove(booking)"
+                  :disabled="processing === booking.id"
+                >
+                  {{ processing === booking.id ? 'Processing...' : 'Approve' }}
+                </button>
+                <button
+                  class="btn btn-sm btn-danger"
+                  @click="showRejectModal(booking)"
+                  :disabled="processing === booking.id"
+                >
+                  Reject
+                </button>
+              </td>
+            </tr>
+          </tbody>
+        </table>
+      </div>
+    </CollapsibleSection>
 
     <!-- Reject Modal -->
     <div v-if="rejectingBooking" class="modal" @click.self="closeRejectModal">
@@ -134,7 +134,7 @@
 
     <!-- Success Message -->
     <div v-if="success" class="card">
-      <div class="success">{{ success }}</div>
+      <div class="success-msg">{{ success }}</div>
     </div>
   </div>
 </template>
@@ -144,6 +144,8 @@ import { ref, computed, onMounted } from 'vue'
 import { adminBookingsApi, spacesApi, handleApiError } from '@/services/api'
 import { useAuthStore } from '@/stores/auth'
 import { formatDate as formatDateUtil, formatTime as formatTimeUtil } from '@/utils/datetime'
+import CollapsibleSection from '@/components/CollapsibleSection.vue'
+import { Filter, ClipboardCheck } from 'lucide-vue-next'
 import type { Booking, Space } from '@/types'
 
 const authStore = useAuthStore()
@@ -279,17 +281,24 @@ onMounted(() => {
 </script>
 
 <style scoped>
-.admin-pending {
-  max-width: 1600px;
-  margin: 0 auto;
+h2 {
+  margin-bottom: 24px;
+  color: var(--color-text-primary);
 }
 
 .card {
-  background: white;
-  border-radius: 8px;
+  background: var(--color-surface);
+  border-radius: var(--radius-md);
   padding: 24px;
-  margin-bottom: 24px;
-  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
+  margin-top: 16px;
+  box-shadow: var(--shadow-sm);
+  border: 1px solid var(--color-border);
+}
+
+.collapsible-section + .collapsible-section,
+.card + .collapsible-section,
+.collapsible-section + .card {
+  margin-top: 16px;
 }
 
 .filters {
@@ -306,22 +315,25 @@ onMounted(() => {
 
 .form-group label {
   font-weight: 500;
-  color: #374151;
+  color: var(--color-text-primary);
+  font-size: 14px;
 }
 
 .form-group select,
 .form-group textarea {
   padding: 8px 12px;
-  border: 1px solid #d1d5db;
-  border-radius: 4px;
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-sm);
   font-size: 14px;
+  background: var(--color-surface);
+  color: var(--color-text-primary);
 }
 
 .form-group select:focus,
 .form-group textarea:focus {
   outline: none;
-  border-color: #3b82f6;
-  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
+  border-color: var(--color-accent);
+  box-shadow: 0 0 0 3px color-mix(in srgb, var(--color-accent) 15%, transparent);
 }
 
 .form-actions {
@@ -332,53 +344,58 @@ onMounted(() => {
 
 .loading {
   text-align: center;
-  color: #6b7280;
+  color: var(--color-text-secondary);
   padding: 24px;
 }
 
 .empty {
   text-align: center;
-  color: #9ca3af;
+  color: var(--color-text-muted);
   padding: 24px;
 }
 
 .error {
   padding: 12px;
-  background: #fee2e2;
-  color: #991b1b;
-  border-radius: 4px;
+  background: color-mix(in srgb, var(--color-danger) 10%, transparent);
+  color: var(--color-danger);
+  border-radius: var(--radius-sm);
 }
 
-.success {
+.success-msg {
   padding: 12px;
-  background: #d1fae5;
-  color: #065f46;
-  border-radius: 4px;
+  background: color-mix(in srgb, var(--color-success) 10%, transparent);
+  color: var(--color-success);
+  border-radius: var(--radius-sm);
 }
 
-.bookings-table {
+.table-responsive {
+  overflow-x: auto;
+}
+
+.data-table {
   width: 100%;
   border-collapse: collapse;
 }
 
-.bookings-table th {
+.data-table th {
   text-align: left;
   padding: 12px;
-  background: #f9fafb;
+  background: var(--color-bg-secondary);
   font-weight: 600;
-  color: #374151;
-  border-bottom: 2px solid #e5e7eb;
+  color: var(--color-text-primary);
+  border-bottom: 2px solid var(--color-border);
   white-space: nowrap;
 }
 
-.bookings-table td {
+.data-table td {
   padding: 12px;
-  border-bottom: 1px solid #e5e7eb;
+  border-bottom: 1px solid var(--color-border);
   vertical-align: top;
+  color: var(--color-text-primary);
 }
 
-.bookings-table tr:hover {
-  background: #f9fafb;
+.data-table tr:hover {
+  background: var(--color-surface-hover);
 }
 
 .user-info,
@@ -391,14 +408,14 @@ onMounted(() => {
 .user-name,
 .space-name {
   font-weight: 500;
-  color: #374151;
+  color: var(--color-text-primary);
 }
 
 .user-email,
 .user-org,
 .space-type {
   font-size: 12px;
-  color: #6b7280;
+  color: var(--color-text-secondary);
 }
 
 .description {
@@ -416,11 +433,11 @@ onMounted(() => {
 .btn {
   padding: 10px 20px;
   border: none;
-  border-radius: 4px;
+  border-radius: var(--radius-sm);
   font-size: 14px;
   font-weight: 500;
   cursor: pointer;
-  transition: all 0.2s;
+  transition: all var(--transition-fast);
 }
 
 .btn:disabled {
@@ -434,30 +451,30 @@ onMounted(() => {
 }
 
 .btn-success {
-  background: #10b981;
+  background: var(--color-success);
   color: white;
 }
 
 .btn-success:hover:not(:disabled) {
-  background: #059669;
+  background: color-mix(in srgb, var(--color-success) 85%, black);
 }
 
 .btn-danger {
-  background: #ef4444;
+  background: var(--color-danger);
   color: white;
 }
 
 .btn-danger:hover:not(:disabled) {
-  background: #dc2626;
+  background: color-mix(in srgb, var(--color-danger) 85%, black);
 }
 
 .btn-secondary {
-  background: #6b7280;
-  color: white;
+  background: var(--color-bg-tertiary);
+  color: var(--color-text-primary);
 }
 
 .btn-secondary:hover:not(:disabled) {
-  background: #4b5563;
+  background: var(--color-border);
 }
 
 .modal {
@@ -474,22 +491,23 @@ onMounted(() => {
 }
 
 .modal-content {
-  background: white;
-  border-radius: 8px;
+  background: var(--color-surface);
+  border-radius: var(--radius-md);
   padding: 24px;
   max-width: 600px;
   width: 90%;
-  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
+  box-shadow: var(--shadow-lg);
 }
 
 .modal-content h3 {
   margin-top: 0;
   margin-bottom: 16px;
+  color: var(--color-text-primary);
 }
 
 .booking-summary {
-  background: #f9fafb;
-  border-radius: 4px;
+  background: var(--color-bg-secondary);
+  border-radius: var(--radius-sm);
   padding: 12px;
   margin-bottom: 16px;
 }
@@ -497,10 +515,10 @@ onMounted(() => {
 .booking-summary p {
   margin: 8px 0;
   font-size: 14px;
-  color: #374151;
+  color: var(--color-text-secondary);
 }
 
 .booking-summary strong {
-  color: #1f2937;
+  color: var(--color-text-primary);
 }
 </style>
diff --git a/frontend/src/views/AdminReports.vue b/frontend/src/views/AdminReports.vue
index af66e53..1df57dd 100644
--- a/frontend/src/views/AdminReports.vue
+++ b/frontend/src/views/AdminReports.vue
@@ -3,20 +3,22 @@
     <h2>Booking Reports</h2>
 
     <!-- Date Range Filter -->
-    <div class="filters">
-      <label>
-        Start Date:
-        <input type="date" v-model="startDate" />
-      </label>
+    <CollapsibleSection title="Date Range Filter" :icon="CalendarDays">
+      <div class="filters">
+        <label>
+          Start Date:
+          <input type="date" v-model="startDate" />
+        </label>
 
-      <label>
-        End Date:
-        <input type="date" v-model="endDate" />
-      </label>
+        <label>
+          End Date:
+          <input type="date" v-model="endDate" />
+        </label>
 
-      <button @click="loadReports" class="btn-primary">Refresh</button>
-      <button @click="clearFilters" class="btn-secondary">Clear Filters</button>
-    </div>
+        <button @click="loadReports" class="btn btn-primary">Refresh</button>
+        <button @click="clearFilters" class="btn btn-secondary">Clear Filters</button>
+      </div>
+    </CollapsibleSection>
 
     <!-- Loading State -->
     <div v-if="loading" class="loading">Loading reports...</div>
@@ -53,63 +55,67 @@
     <div v-if="activeTab === 'usage' && !loading" class="report-content">
       <h3>Space Usage Report</h3>
       <canvas ref="usageChart"></canvas>
-      <table class="report-table">
-        <thead>
-          <tr>
-            <th>Space</th>
-            <th>Total</th>
-            <th>Approved</th>
-            <th>Pending</th>
-            <th>Rejected</th>
-            <th>Canceled</th>
-            <th>Hours</th>
-          </tr>
-        </thead>
-        <tbody>
-          <tr v-for="item in usageReport?.items" :key="item.space_id">
-            <td>{{ item.space_name }}</td>
-            <td>{{ item.total_bookings }}</td>
-            <td class="status-approved">{{ item.approved_bookings }}</td>
-            <td class="status-pending">{{ item.pending_bookings }}</td>
-            <td class="status-rejected">{{ item.rejected_bookings }}</td>
-            <td class="status-canceled">{{ item.canceled_bookings }}</td>
-            <td>{{ item.total_hours.toFixed(1) }}h</td>
-          </tr>
-        </tbody>
-        <tfoot>
-          <tr>
-            <td><strong>Total</strong></td>
-            <td><strong>{{ usageReport?.total_bookings }}</strong></td>
-            <td colspan="5"></td>
-          </tr>
-        </tfoot>
-      </table>
+      <div class="table-responsive">
+        <table class="report-table">
+          <thead>
+            <tr>
+              <th>Space</th>
+              <th>Total</th>
+              <th>Approved</th>
+              <th>Pending</th>
+              <th>Rejected</th>
+              <th>Canceled</th>
+              <th>Hours</th>
+            </tr>
+          </thead>
+          <tbody>
+            <tr v-for="item in usageReport?.items" :key="item.space_id">
+              <td>{{ item.space_name }}</td>
+              <td>{{ item.total_bookings }}</td>
+              <td class="status-approved">{{ item.approved_bookings }}</td>
+              <td class="status-pending">{{ item.pending_bookings }}</td>
+              <td class="status-rejected">{{ item.rejected_bookings }}</td>
+              <td class="status-canceled">{{ item.canceled_bookings }}</td>
+              <td>{{ item.total_hours.toFixed(1) }}h</td>
+            </tr>
+          </tbody>
+          <tfoot>
+            <tr>
+              <td><strong>Total</strong></td>
+              <td><strong>{{ usageReport?.total_bookings }}</strong></td>
+              <td colspan="5"></td>
+            </tr>
+          </tfoot>
+        </table>
+      </div>
     </div>
 
     <!-- Top Users Report -->
     <div v-if="activeTab === 'users' && !loading" class="report-content">
       <h3>Top Users Report</h3>
       <canvas ref="usersChart"></canvas>
-      <table class="report-table">
-        <thead>
-          <tr>
-            <th>User</th>
-            <th>Email</th>
-            <th>Total Bookings</th>
-            <th>Approved</th>
-            <th>Total Hours</th>
-          </tr>
-        </thead>
-        <tbody>
-          <tr v-for="item in topUsersReport?.items" :key="item.user_id">
-            <td>{{ item.user_name }}</td>
-            <td>{{ item.user_email }}</td>
-            <td>{{ item.total_bookings }}</td>
-            <td class="status-approved">{{ item.approved_bookings }}</td>
-            <td>{{ item.total_hours.toFixed(1) }}h</td>
-          </tr>
-        </tbody>
-      </table>
+      <div class="table-responsive">
+        <table class="report-table">
+          <thead>
+            <tr>
+              <th>User</th>
+              <th>Email</th>
+              <th>Total Bookings</th>
+              <th>Approved</th>
+              <th>Total Hours</th>
+            </tr>
+          </thead>
+          <tbody>
+            <tr v-for="item in topUsersReport?.items" :key="item.user_id">
+              <td>{{ item.user_name }}</td>
+              <td>{{ item.user_email }}</td>
+              <td>{{ item.total_bookings }}</td>
+              <td class="status-approved">{{ item.approved_bookings }}</td>
+              <td>{{ item.total_hours.toFixed(1) }}h</td>
+            </tr>
+          </tbody>
+        </table>
+      </div>
     </div>
 
     <!-- Approval Rate Report -->
@@ -144,6 +150,8 @@
 import { ref, onMounted, watch, nextTick } from 'vue'
 import { reportsApi } from '@/services/api'
 import Chart from 'chart.js/auto'
+import CollapsibleSection from '@/components/CollapsibleSection.vue'
+import { CalendarDays } from 'lucide-vue-next'
 import type { SpaceUsageReport, TopUsersReport, ApprovalRateReport } from '@/types'
 
 const activeTab = ref('usage')
@@ -295,25 +303,16 @@ onMounted(() => {
 </script>
 
 <style scoped>
-.admin-reports {
-  padding: 20px;
-  max-width: 1200px;
-  margin: 0 auto;
-}
-
 h2 {
   margin-bottom: 20px;
-  color: #333;
+  color: var(--color-text-primary);
 }
 
 .filters {
   display: flex;
   gap: 15px;
-  margin-bottom: 30px;
   align-items: center;
-  padding: 15px;
-  background: #f5f5f5;
-  border-radius: 8px;
+  flex-wrap: wrap;
 }
 
 .filters label {
@@ -321,58 +320,67 @@ h2 {
   flex-direction: column;
   gap: 5px;
   font-weight: 500;
+  color: var(--color-text-primary);
+  font-size: 14px;
 }
 
 .filters input[type='date'] {
   padding: 8px;
-  border: 1px solid #ddd;
-  border-radius: 4px;
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-sm);
+  background: var(--color-surface);
+  color: var(--color-text-primary);
 }
 
-.btn-primary,
-.btn-secondary {
+.btn {
   padding: 8px 16px;
   border: none;
-  border-radius: 4px;
+  border-radius: var(--radius-sm);
   cursor: pointer;
   font-weight: 500;
+  font-size: 14px;
+  transition: all var(--transition-fast);
 }
 
 .btn-primary {
-  background: #4caf50;
+  background: var(--color-accent);
   color: white;
 }
 
 .btn-primary:hover {
-  background: #45a049;
+  background: var(--color-accent-hover);
 }
 
 .btn-secondary {
-  background: #9e9e9e;
-  color: white;
+  background: var(--color-bg-tertiary);
+  color: var(--color-text-primary);
 }
 
 .btn-secondary:hover {
-  background: #757575;
+  background: var(--color-border);
 }
 
 .loading,
 .error {
   padding: 20px;
   text-align: center;
-  border-radius: 4px;
+  border-radius: var(--radius-sm);
+}
+
+.loading {
+  color: var(--color-text-secondary);
 }
 
 .error {
-  background: #ffebee;
-  color: #c62828;
+  background: color-mix(in srgb, var(--color-danger) 10%, transparent);
+  color: var(--color-danger);
 }
 
 .tabs {
   display: flex;
   gap: 10px;
-  margin-bottom: 20px;
-  border-bottom: 2px solid #ddd;
+  margin: 20px 0;
+  border-bottom: 2px solid var(--color-border);
 }
 
 .tab-button {
@@ -382,29 +390,30 @@ h2 {
   border-bottom: 3px solid transparent;
   cursor: pointer;
   font-weight: 500;
-  color: #666;
-  transition: all 0.3s;
+  color: var(--color-text-secondary);
+  transition: all var(--transition-fast);
 }
 
 .tab-button:hover {
-  color: #333;
+  color: var(--color-text-primary);
 }
 
 .tab-button.active {
-  color: #4caf50;
-  border-bottom-color: #4caf50;
+  color: var(--color-accent);
+  border-bottom-color: var(--color-accent);
 }
 
 .report-content {
-  background: white;
+  background: var(--color-surface);
   padding: 20px;
-  border-radius: 8px;
-  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
+  border-radius: var(--radius-md);
+  box-shadow: var(--shadow-sm);
+  border: 1px solid var(--color-border);
 }
 
 .report-content h3 {
   margin-bottom: 20px;
-  color: #333;
+  color: var(--color-text-primary);
 }
 
 canvas {
@@ -412,6 +421,10 @@ canvas {
   margin-bottom: 30px;
 }
 
+.table-responsive {
+  overflow-x: auto;
+}
+
 .report-table {
   width: 100%;
   border-collapse: collapse;
@@ -422,38 +435,38 @@ canvas {
 .report-table td {
   padding: 12px;
   text-align: left;
-  border-bottom: 1px solid #ddd;
+  border-bottom: 1px solid var(--color-border);
+  color: var(--color-text-primary);
 }
 
 .report-table th {
-  background: #f5f5f5;
+  background: var(--color-bg-secondary);
   font-weight: 600;
-  color: #333;
 }
 
 .report-table tbody tr:hover {
-  background: #f9f9f9;
+  background: var(--color-surface-hover);
 }
 
 .report-table tfoot {
   font-weight: bold;
-  background: #f5f5f5;
+  background: var(--color-bg-secondary);
 }
 
 .status-approved {
-  color: #4caf50;
+  color: var(--color-success);
 }
 
 .status-pending {
-  color: #ffa500;
+  color: var(--color-warning);
 }
 
 .status-rejected {
-  color: #f44336;
+  color: var(--color-danger);
 }
 
 .status-canceled {
-  color: #9e9e9e;
+  color: var(--color-text-muted);
 }
 
 .stats {
@@ -465,8 +478,8 @@ canvas {
 
 .stat-card {
   padding: 20px;
-  background: #f5f5f5;
-  border-radius: 8px;
+  background: var(--color-bg-secondary);
+  border-radius: var(--radius-md);
   text-align: center;
   border: 2px solid transparent;
 }
@@ -474,42 +487,54 @@ canvas {
 .stat-card h3 {
   font-size: 2em;
   margin: 0 0 10px 0;
-  color: #333;
+  color: var(--color-text-primary);
 }
 
 .stat-card p {
   margin: 0;
-  color: #666;
+  color: var(--color-text-secondary);
   font-weight: 500;
 }
 
 .stat-card.approved {
-  background: #e8f5e9;
-  border-color: #4caf50;
+  background: color-mix(in srgb, var(--color-success) 10%, transparent);
+  border-color: var(--color-success);
 }
 
 .stat-card.approved h3 {
-  color: #4caf50;
+  color: var(--color-success);
 }
 
 .stat-card.rejected {
-  background: #ffebee;
-  border-color: #f44336;
+  background: color-mix(in srgb, var(--color-danger) 10%, transparent);
+  border-color: var(--color-danger);
 }
 
 .stat-card.rejected h3 {
-  color: #f44336;
+  color: var(--color-danger);
 }
 
 .breakdown {
   margin-top: 20px;
   padding: 15px;
-  background: #f5f5f5;
-  border-radius: 8px;
+  background: var(--color-bg-secondary);
+  border-radius: var(--radius-md);
 }
 
 .breakdown p {
   margin: 8px 0;
   font-size: 1.1em;
+  color: var(--color-text-primary);
+}
+
+.breakdown strong {
+  color: var(--color-text-primary);
+}
+
+@media (max-width: 768px) {
+  .filters {
+    flex-direction: column;
+    align-items: stretch;
+  }
 }
 </style>
diff --git a/frontend/src/views/AuditLog.vue b/frontend/src/views/AuditLog.vue
index 14f5c06..c58dd76 100644
--- a/frontend/src/views/AuditLog.vue
+++ b/frontend/src/views/AuditLog.vue
@@ -19,55 +19,57 @@
       <input type="date" v-model="filters.start_date" placeholder="Data început" />
       <input type="date" v-model="filters.end_date" placeholder="Data sfârșit" />
 
-      <button @click="loadLogs">Filtrează</button>
-      <button @click="resetFilters">Resetează</button>
+      <button @click="loadLogs" class="btn btn-primary">Filtrează</button>
+      <button @click="resetFilters" class="btn btn-secondary">Resetează</button>
     </div>
 
     <!-- Loading state -->
-    <p v-if="loading">Se încarcă...</p>
+    <p v-if="loading" class="loading-text">Se încarcă...</p>
 
     <!-- Error state -->
     <p v-else-if="error" class="error">{{ error }}</p>
 
     <!-- Table -->
-    <table v-else-if="logs.length > 0">
-      <thead>
-        <tr>
-          <th>Timestamp</th>
-          <th>Utilizator</th>
-          <th>Acțiune</th>
-          <th>Tip Target</th>
-          <th>ID Target</th>
-          <th>Detalii</th>
-        </tr>
-      </thead>
-      <tbody>
-        <tr v-for="log in logs" :key="log.id">
-          <td>{{ formatDate(log.created_at) }}</td>
-          <td>
-            <div>{{ log.user_name }}</div>
-            <small>{{ log.user_email }}</small>
-          </td>
-          <td>{{ formatAction(log.action) }}</td>
-          <td>{{ log.target_type }}</td>
-          <td>{{ log.target_id }}</td>
-          <td>
-            <pre v-if="log.details && Object.keys(log.details).length > 0">{{
-              formatDetails(log.details)
-            }}</pre>
-            <span v-else>-</span>
-          </td>
-        </tr>
-      </tbody>
-    </table>
+    <div v-else-if="logs.length > 0" class="table-responsive">
+      <table class="data-table">
+        <thead>
+          <tr>
+            <th>Timestamp</th>
+            <th>Utilizator</th>
+            <th>Acțiune</th>
+            <th>Tip Target</th>
+            <th>ID Target</th>
+            <th>Detalii</th>
+          </tr>
+        </thead>
+        <tbody>
+          <tr v-for="log in logs" :key="log.id">
+            <td>{{ formatDate(log.created_at) }}</td>
+            <td>
+              <div>{{ log.user_name }}</div>
+              <small>{{ log.user_email }}</small>
+            </td>
+            <td>{{ formatAction(log.action) }}</td>
+            <td>{{ log.target_type }}</td>
+            <td>{{ log.target_id }}</td>
+            <td>
+              <pre v-if="log.details && Object.keys(log.details).length > 0">{{
+                formatDetails(log.details)
+              }}</pre>
+              <span v-else>-</span>
+            </td>
+          </tr>
+        </tbody>
+      </table>
+    </div>
 
-    <p v-else>Nu există înregistrări în jurnal.</p>
+    <p v-else class="empty-text">Nu există înregistrări în jurnal.</p>
 
     <!-- Pagination -->
     <div class="pagination" v-if="logs.length > 0">
-      <button @click="prevPage" :disabled="page === 1">Anterior</button>
+      <button @click="prevPage" :disabled="page === 1" class="btn btn-secondary">Anterior</button>
       <span>Pagina {{ page }}</span>
-      <button @click="nextPage" :disabled="logs.length < limit">Următor</button>
+      <button @click="nextPage" :disabled="logs.length < limit" class="btn btn-secondary">Următor</button>
     </div>
   </div>
 </template>
@@ -158,14 +160,9 @@ onMounted(() => {
 </script>
 
 <style scoped>
-.audit-log {
-  max-width: 1400px;
-  margin: 0 auto;
-  padding: 20px;
-}
-
 h2 {
   margin-bottom: 20px;
+  color: var(--color-text-primary);
 }
 
 .filters {
@@ -179,81 +176,114 @@ h2 {
 .filters select,
 .filters input {
   padding: 8px 12px;
-  border: 1px solid #ddd;
-  border-radius: 4px;
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-sm);
   font-size: 14px;
+  background: var(--color-surface);
+  color: var(--color-text-primary);
 }
 
-.filters button {
+.btn {
   padding: 8px 16px;
-  background-color: #4caf50;
-  color: white;
   border: none;
-  border-radius: 4px;
+  border-radius: var(--radius-sm);
   cursor: pointer;
   font-size: 14px;
+  font-weight: 500;
+  transition: all var(--transition-fast);
 }
 
-.filters button:hover {
-  background-color: #45a049;
+.btn:disabled {
+  opacity: 0.5;
+  cursor: not-allowed;
 }
 
-.filters button:last-child {
-  background-color: #9e9e9e;
+.btn-primary {
+  background: var(--color-accent);
+  color: white;
 }
 
-.filters button:last-child:hover {
-  background-color: #757575;
+.btn-primary:hover:not(:disabled) {
+  background: var(--color-accent-hover);
+}
+
+.btn-secondary {
+  background: var(--color-bg-tertiary);
+  color: var(--color-text-primary);
+}
+
+.btn-secondary:hover:not(:disabled) {
+  background: var(--color-border);
+}
+
+.loading-text {
+  color: var(--color-text-secondary);
+  text-align: center;
+  padding: 20px;
+}
+
+.empty-text {
+  color: var(--color-text-muted);
+  text-align: center;
+  padding: 20px;
 }
 
 .error {
-  color: #f44336;
+  color: var(--color-danger);
   padding: 10px;
-  background-color: #ffebee;
-  border-radius: 4px;
+  background: color-mix(in srgb, var(--color-danger) 10%, transparent);
+  border-radius: var(--radius-sm);
   margin-bottom: 20px;
 }
 
-table {
+.table-responsive {
+  overflow-x: auto;
+}
+
+.data-table {
   width: 100%;
   border-collapse: collapse;
-  background-color: white;
-  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
+  background: var(--color-surface);
+  box-shadow: var(--shadow-sm);
+  border-radius: var(--radius-md);
 }
 
-thead {
-  background-color: #f5f5f5;
+.data-table thead {
+  background: var(--color-bg-secondary);
 }
 
-th {
+.data-table th {
   padding: 12px;
   text-align: left;
   font-weight: 600;
-  border-bottom: 2px solid #e0e0e0;
+  color: var(--color-text-primary);
+  border-bottom: 2px solid var(--color-border);
 }
 
-td {
+.data-table td {
   padding: 12px;
-  border-bottom: 1px solid #e0e0e0;
+  border-bottom: 1px solid var(--color-border);
+  color: var(--color-text-primary);
 }
 
-td small {
-  color: #757575;
+.data-table td small {
+  color: var(--color-text-secondary);
   font-size: 12px;
 }
 
-tbody tr:hover {
-  background-color: #f9f9f9;
+.data-table tbody tr:hover {
+  background: var(--color-surface-hover);
 }
 
 pre {
   margin: 0;
   padding: 8px;
-  background-color: #f5f5f5;
-  border-radius: 4px;
+  background: var(--color-bg-secondary);
+  border-radius: var(--radius-sm);
   font-size: 12px;
   overflow-x: auto;
   max-width: 300px;
+  color: var(--color-text-primary);
 }
 
 .pagination {
@@ -264,25 +294,20 @@ pre {
   margin-top: 20px;
 }
 
-.pagination button {
-  padding: 8px 16px;
-  background-color: #2196f3;
-  color: white;
-  border: none;
-  border-radius: 4px;
-  cursor: pointer;
-}
-
-.pagination button:hover:not(:disabled) {
-  background-color: #1976d2;
-}
-
-.pagination button:disabled {
-  background-color: #e0e0e0;
-  cursor: not-allowed;
-}
-
 .pagination span {
   font-weight: 500;
+  color: var(--color-text-primary);
+}
+
+@media (max-width: 768px) {
+  .filters {
+    flex-direction: column;
+  }
+
+  .filters select,
+  .filters input,
+  .btn {
+    width: 100%;
+  }
 }
 </style>
diff --git a/frontend/src/views/Dashboard.vue b/frontend/src/views/Dashboard.vue
index c0a6f9b..bdc8595 100644
--- a/frontend/src/views/Dashboard.vue
+++ b/frontend/src/views/Dashboard.vue
@@ -11,126 +11,72 @@
     <!-- Dashboard Content -->
     <div v-else class="dashboard-content">
       <!-- Quick Stats -->
-      <div class="stats-grid">
-        <div class="stat-card">
-          <div class="stat-icon stat-icon-total">
-            <svg fill="none" stroke="currentColor" viewBox="0 0 24 24">
-              <path
-                stroke-linecap="round"
-                stroke-linejoin="round"
-                stroke-width="2"
-                d="M8 7V3m8 4V3m-9 8h10M5 21h14a2 2 0 002-2V7a2 2 0 00-2-2H5a2 2 0 00-2 2v12a2 2 0 002 2z"
-              />
-            </svg>
+      <CollapsibleSection title="Quick Stats" :icon="BarChart3">
+        <div class="stats-grid">
+          <div class="stat-card">
+            <div class="stat-icon stat-icon-total">
+              <Calendar :size="28" />
+            </div>
+            <div class="stat-content">
+              <h3>{{ stats.total }}</h3>
+              <p>Total Bookings</p>
+            </div>
           </div>
-          <div class="stat-content">
-            <h3>{{ stats.total }}</h3>
-            <p>Total Bookings</p>
-          </div>
-        </div>
 
-        <div class="stat-card">
-          <div class="stat-icon stat-icon-pending">
-            <svg fill="none" stroke="currentColor" viewBox="0 0 24 24">
-              <path
-                stroke-linecap="round"
-                stroke-linejoin="round"
-                stroke-width="2"
-                d="M12 8v4l3 3m6-3a9 9 0 11-18 0 9 9 0 0118 0z"
-              />
-            </svg>
+          <div class="stat-card">
+            <div class="stat-icon stat-icon-pending">
+              <Clock :size="28" />
+            </div>
+            <div class="stat-content">
+              <h3>{{ stats.pending }}</h3>
+              <p>Pending</p>
+            </div>
           </div>
-          <div class="stat-content">
-            <h3>{{ stats.pending }}</h3>
-            <p>Pending</p>
-          </div>
-        </div>
 
-        <div class="stat-card">
-          <div class="stat-icon stat-icon-approved">
-            <svg fill="none" stroke="currentColor" viewBox="0 0 24 24">
-              <path
-                stroke-linecap="round"
-                stroke-linejoin="round"
-                stroke-width="2"
-                d="M9 12l2 2 4-4m6 2a9 9 0 11-18 0 9 9 0 0118 0z"
-              />
-            </svg>
+          <div class="stat-card">
+            <div class="stat-icon stat-icon-approved">
+              <CheckCircle :size="28" />
+            </div>
+            <div class="stat-content">
+              <h3>{{ stats.approved }}</h3>
+              <p>Approved</p>
+            </div>
           </div>
-          <div class="stat-content">
-            <h3>{{ stats.approved }}</h3>
-            <p>Approved</p>
-          </div>
-        </div>
 
-        <!-- Admin: Pending Requests -->
-        <div v-if="isAdmin" class="stat-card">
-          <div class="stat-icon stat-icon-admin">
-            <svg fill="none" stroke="currentColor" viewBox="0 0 24 24">
-              <path
-                stroke-linecap="round"
-                stroke-linejoin="round"
-                stroke-width="2"
-                d="M12 4.354a4 4 0 110 5.292M15 21H3v-1a6 6 0 0112 0v1zm0 0h6v-1a6 6 0 00-9-5.197M13 7a4 4 0 11-8 0 4 4 0 018 0z"
-              />
-            </svg>
-          </div>
-          <div class="stat-content">
-            <h3>{{ adminStats.pendingRequests }}</h3>
-            <p>Pending Requests</p>
+          <!-- Admin: Pending Requests -->
+          <div v-if="isAdmin" class="stat-card">
+            <div class="stat-icon stat-icon-admin">
+              <Users :size="28" />
+            </div>
+            <div class="stat-content">
+              <h3>{{ adminStats.pendingRequests }}</h3>
+              <p>Pending Requests</p>
+            </div>
           </div>
         </div>
-      </div>
+      </CollapsibleSection>
 
       <!-- Quick Actions -->
       <div class="card quick-actions">
         <h3>Quick Actions</h3>
         <div class="actions-grid">
           <router-link to="/spaces" class="action-btn">
-            <svg class="icon" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-              <path
-                stroke-linecap="round"
-                stroke-linejoin="round"
-                stroke-width="2"
-                d="M21 21l-6-6m2-5a7 7 0 11-14 0 7 7 0 0114 0z"
-              />
-            </svg>
+            <Search :size="24" class="action-icon" />
             <span>Book a Space</span>
           </router-link>
 
           <router-link to="/my-bookings" class="action-btn">
-            <svg class="icon" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-              <path
-                stroke-linecap="round"
-                stroke-linejoin="round"
-                stroke-width="2"
-                d="M9 5H7a2 2 0 00-2 2v12a2 2 0 002 2h10a2 2 0 002-2V7a2 2 0 00-2-2h-2M9 5a2 2 0 002 2h2a2 2 0 002-2M9 5a2 2 0 012-2h2a2 2 0 012 2"
-              />
-            </svg>
+            <ClipboardList :size="24" class="action-icon" />
             <span>My Bookings</span>
           </router-link>
 
           <router-link v-if="isAdmin" to="/admin/bookings" class="action-btn">
-            <svg class="icon" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-              <path
-                stroke-linecap="round"
-                stroke-linejoin="round"
-                stroke-width="2"
-                d="M9 5H7a2 2 0 00-2 2v12a2 2 0 002 2h10a2 2 0 002-2V7a2 2 0 00-2-2h-2M9 5a2 2 0 002 2h2a2 2 0 002-2M9 5a2 2 0 012-2h2a2 2 0 012 2m-6 9l2 2 4-4"
-              />
-            </svg>
+            <ClipboardCheck :size="24" class="action-icon" />
             <span>Manage Bookings</span>
           </router-link>
 
           <router-link v-if="isAdmin" to="/admin/spaces" class="action-btn">
-            <svg class="icon" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-              <path
-                stroke-linecap="round"
-                stroke-linejoin="round"
-                stroke-width="2"
-                d="M19 21V5a2 2 0 00-2-2H7a2 2 0 00-2 2v16m14 0h2m-2 0h-5m-9 0H3m2 0h5M9 7h1m-1 4h1m4-4h1m-1 4h1m-5 10v-5a1 1 0 011-1h2a1 1 0 011 1v5m-4 0h4"
-              />
-            </svg>
+            <Building2 :size="24" class="action-icon" />
             <span>Manage Spaces</span>
           </router-link>
         </div>
@@ -138,21 +84,13 @@
 
       <div class="content-grid">
         <!-- Upcoming Bookings -->
-        <div class="card">
-          <div class="card-header">
-            <h3>Upcoming Bookings</h3>
+        <CollapsibleSection title="Upcoming Bookings" :icon="CalendarDays">
+          <template #header-actions>
             <router-link to="/my-bookings" class="link">View All</router-link>
-          </div>
+          </template>
 
           <div v-if="upcomingBookings.length === 0" class="empty-state-small">
-            <svg class="icon-empty" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-              <path
-                stroke-linecap="round"
-                stroke-linejoin="round"
-                stroke-width="2"
-                d="M8 7V3m8 4V3m-9 8h10M5 21h14a2 2 0 002-2V7a2 2 0 00-2-2H5a2 2 0 00-2 2v12a2 2 0 002 2z"
-              />
-            </svg>
+            <Calendar :size="48" class="icon-empty" />
             <p>No upcoming bookings</p>
           </div>
 
@@ -163,14 +101,7 @@
               class="booking-item"
             >
               <div class="booking-icon">
-                <svg fill="none" stroke="currentColor" viewBox="0 0 24 24">
-                  <path
-                    stroke-linecap="round"
-                    stroke-linejoin="round"
-                    stroke-width="2"
-                    d="M8 7V3m8 4V3m-9 8h10M5 21h14a2 2 0 002-2V7a2 2 0 00-2-2H5a2 2 0 00-2 2v12a2 2 0 002 2z"
-                  />
-                </svg>
+                <Calendar :size="20" />
               </div>
               <div class="booking-info">
                 <h4>{{ booking.title }}</h4>
@@ -184,24 +115,16 @@
               </span>
             </div>
           </div>
-        </div>
+        </CollapsibleSection>
 
         <!-- Available Spaces -->
-        <div class="card">
-          <div class="card-header">
-            <h3>Available Spaces</h3>
+        <CollapsibleSection title="Available Spaces" :icon="Building2">
+          <template #header-actions>
             <router-link to="/spaces" class="link">View All</router-link>
-          </div>
+          </template>
 
           <div v-if="availableSpaces.length === 0" class="empty-state-small">
-            <svg class="icon-empty" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-              <path
-                stroke-linecap="round"
-                stroke-linejoin="round"
-                stroke-width="2"
-                d="M19 21V5a2 2 0 00-2-2H7a2 2 0 00-2 2v16m14 0h2m-2 0h-5m-9 0H3m2 0h5M9 7h1m-1 4h1m4-4h1m-1 4h1m-5 10v-5a1 1 0 011-1h2a1 1 0 011 1v5m-4 0h4"
-              />
-            </svg>
+            <Building2 :size="48" class="icon-empty" />
             <p>No available spaces</p>
           </div>
 
@@ -213,14 +136,7 @@
               class="space-item"
             >
               <div class="space-icon">
-                <svg fill="none" stroke="currentColor" viewBox="0 0 24 24">
-                  <path
-                    stroke-linecap="round"
-                    stroke-linejoin="round"
-                    stroke-width="2"
-                    d="M19 21V5a2 2 0 00-2-2H7a2 2 0 00-2 2v16m14 0h2m-2 0h-5m-9 0H3m2 0h5M9 7h1m-1 4h1m4-4h1m-1 4h1m-5 10v-5a1 1 0 011-1h2a1 1 0 011 1v5m-4 0h4"
-                  />
-                </svg>
+                <Building2 :size="20" />
               </div>
               <div class="space-info">
                 <h4>{{ space.name }}</h4>
@@ -228,25 +144,17 @@
                   {{ formatType(space.type) }} · Capacity: {{ space.capacity }}
                 </p>
               </div>
-              <svg class="icon-chevron" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-                <path
-                  stroke-linecap="round"
-                  stroke-linejoin="round"
-                  stroke-width="2"
-                  d="M9 5l7 7-7 7"
-                />
-              </svg>
+              <ChevronRight :size="20" class="icon-chevron" />
             </router-link>
           </div>
-        </div>
+        </CollapsibleSection>
       </div>
 
       <!-- Admin: Recent Audit Logs -->
-      <div v-if="isAdmin" class="card">
-        <div class="card-header">
-          <h3>Recent Activity</h3>
+      <CollapsibleSection v-if="isAdmin" title="Recent Activity" :icon="ScrollText">
+        <template #header-actions>
           <router-link to="/admin/audit-log" class="link">View All</router-link>
-        </div>
+        </template>
 
         <div v-if="recentAuditLogs.length === 0" class="empty-state-small">
           <p>No recent activity</p>
@@ -255,14 +163,7 @@
         <div v-else class="audit-list">
           <div v-for="log in recentAuditLogs" :key="log.id" class="audit-item">
             <div class="audit-icon">
-              <svg fill="none" stroke="currentColor" viewBox="0 0 24 24">
-                <path
-                  stroke-linecap="round"
-                  stroke-linejoin="round"
-                  stroke-width="2"
-                  d="M9 12h6m-6 4h6m2 5H7a2 2 0 01-2-2V5a2 2 0 012-2h5.586a1 1 0 01.707.293l5.414 5.414a1 1 0 01.293.707V19a2 2 0 01-2 2z"
-                />
-              </svg>
+              <FileText :size="20" />
             </div>
             <div class="audit-info">
               <p class="audit-action">{{ log.action }}</p>
@@ -271,7 +172,7 @@
             </div>
           </div>
         </div>
-      </div>
+      </CollapsibleSection>
     </div>
   </div>
 </template>
@@ -288,6 +189,22 @@ import {
 } from '@/services/api'
 import { useAuthStore } from '@/stores/auth'
 import { formatDateTime as formatDateTimeUtil, ensureUTC } from '@/utils/datetime'
+import CollapsibleSection from '@/components/CollapsibleSection.vue'
+import {
+  Calendar,
+  CalendarDays,
+  Clock,
+  CheckCircle,
+  Users,
+  Search,
+  ClipboardList,
+  ClipboardCheck,
+  Building2,
+  ChevronRight,
+  FileText,
+  ScrollText,
+  BarChart3
+} from 'lucide-vue-next'
 import type { Space, Booking, AuditLog, User } from '@/types'
 
 const authStore = useAuthStore()
@@ -402,15 +319,10 @@ onMounted(() => {
 </script>
 
 <style scoped>
-.dashboard {
-  max-width: 1400px;
-  margin: 0 auto;
-}
-
 .dashboard h2 {
   font-size: 32px;
   font-weight: 700;
-  color: #111827;
+  color: var(--color-text-primary);
   margin-bottom: 32px;
 }
 
@@ -421,14 +333,14 @@ onMounted(() => {
   align-items: center;
   justify-content: center;
   padding: 80px 20px;
-  color: #6b7280;
+  color: var(--color-text-secondary);
 }
 
 .spinner {
   width: 48px;
   height: 48px;
-  border: 4px solid #e5e7eb;
-  border-top-color: #3b82f6;
+  border: 4px solid var(--color-border);
+  border-top-color: var(--color-accent);
   border-radius: 50%;
   animation: spin 0.8s linear infinite;
   margin-bottom: 16px;
@@ -444,21 +356,21 @@ onMounted(() => {
 .dashboard-content {
   display: flex;
   flex-direction: column;
-  gap: 32px;
+  gap: 24px;
 }
 
 /* Stats Grid */
 .stats-grid {
   display: grid;
-  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
-  gap: 20px;
+  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
+  gap: 16px;
 }
 
 .stat-card {
-  background: white;
-  border-radius: 8px;
-  padding: 24px;
-  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
+  background: var(--color-surface);
+  border-radius: var(--radius-md);
+  padding: 20px;
+  border: 1px solid var(--color-border-light);
   display: flex;
   align-items: center;
   gap: 16px;
@@ -467,53 +379,49 @@ onMounted(() => {
 .stat-icon {
   width: 56px;
   height: 56px;
-  border-radius: 12px;
+  border-radius: var(--radius-lg);
   display: flex;
   align-items: center;
   justify-content: center;
   flex-shrink: 0;
 }
 
-.stat-icon svg {
-  width: 28px;
-  height: 28px;
-}
-
 .stat-icon-total {
-  background: #dbeafe;
-  color: #1e40af;
+  background: var(--color-accent-light);
+  color: var(--color-info);
 }
 
 .stat-icon-pending {
-  background: #fef3c7;
-  color: #92400e;
+  background: color-mix(in srgb, var(--color-warning) 15%, transparent);
+  color: var(--color-warning);
 }
 
 .stat-icon-approved {
-  background: #d1fae5;
-  color: #065f46;
+  background: color-mix(in srgb, var(--color-success) 15%, transparent);
+  color: var(--color-success);
 }
 
 .stat-icon-admin {
-  background: #e0e7ff;
-  color: #3730a3;
+  background: var(--color-accent-light);
+  color: var(--color-accent);
 }
 
 .stat-content h3 {
   font-size: 32px;
   font-weight: 700;
-  color: #111827;
+  color: var(--color-text-primary);
   margin-bottom: 4px;
 }
 
 .stat-content p {
-  color: #6b7280;
+  color: var(--color-text-secondary);
   font-size: 14px;
 }
 
 /* Quick Actions */
 .quick-actions h3 {
   margin-bottom: 20px;
+  color: var(--color-text-primary);
 }
 
 .actions-grid {
@@ -527,23 +435,21 @@ onMounted(() => {
   align-items: center;
   gap: 12px;
   padding: 16px 20px;
-  background: #f3f4f6;
-  border-radius: 8px;
-  color: #374151;
+  background: var(--color-bg-secondary);
+  border-radius: var(--radius-md);
+  color: var(--color-text-primary);
   text-decoration: none;
   font-weight: 600;
-  transition: all 0.2s;
+  transition: all var(--transition-fast);
 }
 
 .action-btn:hover {
-  background: #e5e7eb;
+  background: var(--color-bg-tertiary);
   transform: translateY(-2px);
 }
 
-.action-btn .icon {
-  width: 24px;
-  height: 24px;
-  color: #3b82f6;
+.action-icon {
+  color: var(--color-accent);
 }
 
 /* Content Grid */
@@ -555,35 +461,23 @@ onMounted(() => {
 
 /* Cards */
 .card {
-  background: white;
-  border-radius: 8px;
+  background: var(--color-surface);
+  border-radius: var(--radius-md);
   padding: 24px;
-  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
-}
-
-.card-header {
-  display: flex;
-  justify-content: space-between;
-  align-items: center;
-  margin-bottom: 20px;
-}
-
-.card h3 {
-  font-size: 20px;
-  font-weight: 600;
-  color: #111827;
+  box-shadow: var(--shadow-sm);
+  border: 1px solid var(--color-border);
 }
 
 .link {
-  color: #3b82f6;
+  color: var(--color-accent);
   text-decoration: none;
   font-size: 14px;
   font-weight: 500;
-  transition: color 0.2s;
+  transition: color var(--transition-fast);
 }
 
 .link:hover {
-  color: #2563eb;
+  color: var(--color-accent-hover);
   text-decoration: underline;
 }
 
@@ -591,18 +485,17 @@ onMounted(() => {
 .empty-state-small {
   text-align: center;
   padding: 40px 20px;
-  color: #9ca3af;
+  color: var(--color-text-muted);
 }
 
 .icon-empty {
-  width: 48px;
-  height: 48px;
   margin: 0 auto 12px;
-  color: #d1d5db;
+  color: var(--color-border);
+  display: block;
 }
 
 .empty-state-small p {
-  color: #6b7280;
+  color: var(--color-text-secondary);
   font-size: 14px;
 }
 
@@ -610,38 +503,33 @@ onMounted(() => {
 .bookings-list {
   display: flex;
   flex-direction: column;
-  gap: 16px;
+  gap: 12px;
 }
 
 .booking-item {
   display: flex;
   align-items: flex-start;
   gap: 12px;
-  padding: 16px;
-  background: #f9fafb;
-  border-radius: 8px;
-  transition: background 0.2s;
+  padding: 14px;
+  background: var(--color-bg-secondary);
+  border-radius: var(--radius-md);
+  transition: background var(--transition-fast);
 }
 
 .booking-item:hover {
-  background: #f3f4f6;
+  background: var(--color-bg-tertiary);
 }
 
 .booking-icon {
   width: 40px;
   height: 40px;
-  background: white;
-  border-radius: 8px;
+  background: var(--color-surface);
+  border-radius: var(--radius-md);
   display: flex;
   align-items: center;
   justify-content: center;
   flex-shrink: 0;
-}
-
-.booking-icon svg {
-  width: 20px;
-  height: 20px;
-  color: #3b82f6;
+  color: var(--color-accent);
 }
 
 .booking-info {
@@ -651,86 +539,53 @@ onMounted(() => {
 .booking-info h4 {
   font-size: 16px;
   font-weight: 600;
-  color: #111827;
+  color: var(--color-text-primary);
   margin-bottom: 4px;
 }
 
 .booking-space {
   font-size: 14px;
-  color: #6b7280;
+  color: var(--color-text-secondary);
   margin-bottom: 2px;
 }
 
 .booking-time {
   font-size: 13px;
-  color: #9ca3af;
-}
-
-.badge {
-  padding: 4px 12px;
-  border-radius: 12px;
-  font-size: 12px;
-  font-weight: 500;
-  white-space: nowrap;
-}
-
-.badge-pending {
-  background: #fef3c7;
-  color: #92400e;
-}
-
-.badge-approved {
-  background: #d1fae5;
-  color: #065f46;
-}
-
-.badge-rejected {
-  background: #fee2e2;
-  color: #991b1b;
-}
-
-.badge-canceled {
-  background: #e5e7eb;
-  color: #4b5563;
+  color: var(--color-text-muted);
 }
 
 /* Spaces List */
 .spaces-list {
   display: flex;
   flex-direction: column;
-  gap: 12px;
+  gap: 8px;
 }
 
 .space-item {
   display: flex;
   align-items: center;
   gap: 12px;
-  padding: 16px;
-  background: #f9fafb;
-  border-radius: 8px;
+  padding: 14px;
+  background: var(--color-bg-secondary);
+  border-radius: var(--radius-md);
   text-decoration: none;
-  transition: background 0.2s;
+  transition: background var(--transition-fast);
 }
 
 .space-item:hover {
-  background: #f3f4f6;
+  background: var(--color-bg-tertiary);
 }
 
 .space-icon {
   width: 40px;
   height: 40px;
-  background: white;
-  border-radius: 8px;
+  background: var(--color-surface);
+  border-radius: var(--radius-md);
   display: flex;
   align-items: center;
   justify-content: center;
   flex-shrink: 0;
-}
-
-.space-icon svg {
-  width: 20px;
-  height: 20px;
-  color: #3b82f6;
+  color: var(--color-accent);
 }
 
 .space-info {
@@ -740,51 +595,44 @@ onMounted(() => {
 .space-info h4 {
   font-size: 16px;
   font-weight: 600;
-  color: #111827;
+  color: var(--color-text-primary);
   margin-bottom: 2px;
 }
 
 .space-meta {
   font-size: 13px;
-  color: #6b7280;
+  color: var(--color-text-secondary);
 }
 
 .icon-chevron {
-  width: 20px;
-  height: 20px;
-  color: #9ca3af;
+  color: var(--color-text-muted);
 }
 
 /* Audit List */
 .audit-list {
   display: flex;
   flex-direction: column;
-  gap: 16px;
+  gap: 12px;
 }
 
 .audit-item {
   display: flex;
   gap: 12px;
-  padding: 16px;
-  background: #f9fafb;
-  border-radius: 8px;
+  padding: 14px;
+  background: var(--color-bg-secondary);
+  border-radius: var(--radius-md);
 }
 
 .audit-icon {
   width: 40px;
   height: 40px;
-  background: white;
-  border-radius: 8px;
+  background: var(--color-surface);
+  border-radius: var(--radius-md);
   display: flex;
   align-items: center;
   justify-content: center;
   flex-shrink: 0;
-}
-
-.audit-icon svg {
-  width: 20px;
-  height: 20px;
-  color: #6b7280;
+  color: var(--color-text-secondary);
 }
 
 .audit-info {
@@ -794,19 +642,19 @@ onMounted(() => {
 .audit-action {
   font-size: 14px;
   font-weight: 600;
-  color: #111827;
+  color: var(--color-text-primary);
   margin-bottom: 4px;
 }
 
 .audit-user {
   font-size: 13px;
-  color: #6b7280;
+  color: var(--color-text-secondary);
   margin-bottom: 2px;
 }
 
 .audit-time {
   font-size: 12px;
-  color: #9ca3af;
+  color: var(--color-text-muted);
 }
 
 /* Responsive */
diff --git a/frontend/src/views/Login.vue b/frontend/src/views/Login.vue
index f8155a3..545e8e9 100644
--- a/frontend/src/views/Login.vue
+++ b/frontend/src/views/Login.vue
@@ -100,12 +100,12 @@ const handleLogin = async () => {
 h2 {
   text-align: center;
   margin-bottom: 0.5rem;
-  color: #2c3e50;
+  color: var(--color-text-primary);
 }
 
 .subtitle {
   text-align: center;
-  color: #7f8c8d;
+  color: var(--color-text-secondary);
   margin-bottom: 2rem;
 }
 
@@ -117,11 +117,11 @@ h2 {
 .register-link {
   text-align: center;
   margin-top: 1.5rem;
-  color: #7f8c8d;
+  color: var(--color-text-secondary);
 }
 
 .register-link a {
-  color: #3498db;
+  color: var(--color-accent);
   text-decoration: none;
 }
 
@@ -132,15 +132,15 @@ h2 {
 .demo-accounts {
   margin-top: 2rem;
   padding-top: 1.5rem;
-  border-top: 1px solid #e1e8ed;
+  border-top: 1px solid var(--color-border);
   font-size: 0.9rem;
-  color: #7f8c8d;
+  color: var(--color-text-secondary);
 }
 
 .demo-title {
   font-weight: 600;
   margin-bottom: 0.5rem;
-  color: #2c3e50;
+  color: var(--color-text-primary);
 }
 
 .demo-accounts p {
@@ -150,8 +150,9 @@ h2 {
 .error {
   margin-top: 1rem;
   padding: 0.75rem;
-  background: #fee;
-  border-left: 3px solid #e74c3c;
-  border-radius: 4px;
+  background: color-mix(in srgb, var(--color-danger) 10%, transparent);
+  border-left: 3px solid var(--color-danger);
+  border-radius: var(--radius-sm);
+  color: var(--color-danger);
 }
 </style>
diff --git a/frontend/src/views/MyBookings.vue b/frontend/src/views/MyBookings.vue
index 6f47dff..58e4b2c 100644
--- a/frontend/src/views/MyBookings.vue
+++ b/frontend/src/views/MyBookings.vue
@@ -297,11 +297,9 @@ const formatStatus = (status: string): string => {
 const openEditModal = (booking: Booking) => {
   editingBooking.value = booking
 
-  // Extract date and time from ISO datetime
   const startLocal = isoToLocalDateTime(booking.start_datetime, userTimezone.value)
   const endLocal = isoToLocalDateTime(booking.end_datetime, userTimezone.value)
 
-  // Split YYYY-MM-DDTHH:mm into date and time parts
   const [startDate, startTime] = startLocal.split('T')
   const [endDate, endTime] = endLocal.split('T')
 
@@ -330,7 +328,6 @@ const saveEdit = async () => {
   editError.value = ''
 
   try {
-    // Combine date and time, then convert to ISO
     const startDateTime = `${editForm.value.start_date}T${editForm.value.start_time}`
     const endDateTime = `${editForm.value.end_date}T${editForm.value.end_time}`
 
@@ -352,7 +349,6 @@ const saveEdit = async () => {
 }
 
 const canCancel = (booking: Booking): boolean => {
-  // Can only cancel pending or approved bookings
   return booking.status === 'pending' || booking.status === 'approved'
 }
 
@@ -365,9 +361,6 @@ const handleCancel = async (booking: Booking) => {
   error.value = ''
 
   try {
-    // TODO: Implement cancel endpoint when available
-    // await bookingsApi.cancel(booking.id)
-    // For now, just show a message
     alert('Cancel functionality will be implemented in a future update.')
     await loadBookings()
   } catch (err) {
@@ -383,17 +376,18 @@ onMounted(() => {
 </script>
 
 <style scoped>
-.my-bookings {
-  max-width: 1400px;
-  margin: 0 auto;
+h2 {
+  margin-bottom: 24px;
+  color: var(--color-text-primary);
 }
 
 .card {
-  background: white;
-  border-radius: 8px;
+  background: var(--color-surface);
+  border-radius: var(--radius-md);
   padding: 24px;
   margin-bottom: 24px;
-  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
+  box-shadow: var(--shadow-sm);
+  border: 1px solid var(--color-border);
 }
 
 .filter-card {
@@ -408,34 +402,35 @@ onMounted(() => {
 
 .filter-group label {
   font-weight: 500;
-  color: #374151;
+  color: var(--color-text-primary);
 }
 
 .filter-group select {
   padding: 8px 12px;
-  border: 1px solid #d1d5db;
-  border-radius: 4px;
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-sm);
   font-size: 14px;
   cursor: pointer;
-  background: white;
+  background: var(--color-surface);
+  color: var(--color-text-primary);
   min-width: 150px;
 }
 
 .filter-group select:focus {
   outline: none;
-  border-color: #3b82f6;
-  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
+  border-color: var(--color-accent);
+  box-shadow: 0 0 0 3px color-mix(in srgb, var(--color-accent) 15%, transparent);
 }
 
 .loading {
   text-align: center;
-  color: #6b7280;
+  color: var(--color-text-secondary);
   padding: 24px;
 }
 
 .empty {
   text-align: center;
-  color: #9ca3af;
+  color: var(--color-text-muted);
   padding: 24px;
   display: flex;
   flex-direction: column;
@@ -445,9 +440,9 @@ onMounted(() => {
 
 .error {
   padding: 12px;
-  background: #fee2e2;
-  color: #991b1b;
-  border-radius: 4px;
+  background: color-mix(in srgb, var(--color-danger) 10%, transparent);
+  color: var(--color-danger);
+  border-radius: var(--radius-sm);
 }
 
 .bookings-table {
@@ -459,20 +454,21 @@ onMounted(() => {
 .bookings-table th {
   text-align: left;
   padding: 12px;
-  background: #f9fafb;
+  background: var(--color-bg-secondary);
   font-weight: 600;
-  color: #374151;
-  border-bottom: 2px solid #e5e7eb;
+  color: var(--color-text-primary);
+  border-bottom: 2px solid var(--color-border);
 }
 
 .bookings-table td {
   padding: 12px;
-  border-bottom: 1px solid #e5e7eb;
+  border-bottom: 1px solid var(--color-border);
   vertical-align: middle;
+  color: var(--color-text-primary);
 }
 
 .bookings-table tr:hover {
-  background: #f9fafb;
+  background: var(--color-surface-hover);
 }
 
 .space-info {
@@ -483,12 +479,12 @@ onMounted(() => {
 
 .space-name {
   font-weight: 500;
-  color: #374151;
+  color: var(--color-text-primary);
 }
 
 .space-type {
   font-size: 12px;
-  color: #6b7280;
+  color: var(--color-text-secondary);
 }
 
 .badge {
@@ -500,23 +496,23 @@ onMounted(() => {
 }
 
 .badge-pending {
-  background: #fef3c7;
-  color: #92400e;
+  background: color-mix(in srgb, var(--color-warning) 15%, transparent);
+  color: var(--color-warning);
 }
 
 .badge-approved {
-  background: #d1fae5;
-  color: #065f46;
+  background: color-mix(in srgb, var(--color-success) 15%, transparent);
+  color: var(--color-success);
 }
 
 .badge-rejected {
-  background: #fee2e2;
-  color: #991b1b;
+  background: color-mix(in srgb, var(--color-danger) 15%, transparent);
+  color: var(--color-danger);
 }
 
 .badge-canceled {
-  background: #f3f4f6;
-  color: #6b7280;
+  background: var(--color-bg-tertiary);
+  color: var(--color-text-secondary);
 }
 
 .actions {
@@ -525,17 +521,17 @@ onMounted(() => {
 }
 
 .no-action {
-  color: #9ca3af;
+  color: var(--color-text-muted);
 }
 
 .btn {
   padding: 10px 20px;
   border: none;
-  border-radius: 4px;
+  border-radius: var(--radius-sm);
   font-size: 14px;
   font-weight: 500;
   cursor: pointer;
-  transition: all 0.2s;
+  transition: all var(--transition-fast);
   text-decoration: none;
   display: inline-block;
 }
@@ -546,21 +542,30 @@ onMounted(() => {
 }
 
 .btn-primary {
-  background: #3b82f6;
+  background: var(--color-accent);
   color: white;
 }
 
 .btn-primary:hover:not(:disabled) {
-  background: #2563eb;
+  background: var(--color-accent-hover);
 }
 
 .btn-danger {
-  background: #ef4444;
+  background: var(--color-danger);
   color: white;
 }
 
 .btn-danger:hover:not(:disabled) {
-  background: #dc2626;
+  background: color-mix(in srgb, var(--color-danger) 85%, black);
+}
+
+.btn-secondary {
+  background: var(--color-bg-tertiary);
+  color: var(--color-text-primary);
+}
+
+.btn-secondary:hover:not(:disabled) {
+  background: var(--color-border);
 }
 
 .btn-sm {
@@ -591,18 +596,19 @@ onMounted(() => {
 }
 
 .modal-content {
-  background: white;
-  border-radius: 8px;
+  background: var(--color-surface);
+  border-radius: var(--radius-md);
   padding: 24px;
   max-width: 500px;
   width: 90%;
   max-height: 90vh;
   overflow-y: auto;
+  box-shadow: var(--shadow-lg);
 }
 
 .modal-content h3 {
   margin: 0 0 20px 0;
-  color: #374151;
+  color: var(--color-text-primary);
 }
 
 .form-group {
@@ -613,14 +619,14 @@ onMounted(() => {
   display: block;
   margin-bottom: 6px;
   font-weight: 500;
-  color: #374151;
+  color: var(--color-text-primary);
 }
 
 .form-label {
   display: block;
   margin-bottom: 8px;
   font-weight: 500;
-  color: #374151;
+  color: var(--color-text-primary);
   font-size: 14px;
 }
 
@@ -628,7 +634,7 @@ onMounted(() => {
   display: block;
   margin-bottom: 4px;
   font-weight: 400;
-  color: #6b7280;
+  color: var(--color-text-secondary);
   font-size: 12px;
 }
 
@@ -647,17 +653,24 @@ onMounted(() => {
 .form-group textarea {
   width: 100%;
   padding: 8px 12px;
-  border: 1px solid #d1d5db;
-  border-radius: 4px;
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-sm);
   font-size: 14px;
   font-family: inherit;
+  background: var(--color-surface);
+  color: var(--color-text-primary);
 }
 
 .form-group input:focus,
 .form-group textarea:focus {
   outline: none;
-  border-color: #3b82f6;
-  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
+  border-color: var(--color-accent);
+  box-shadow: 0 0 0 3px color-mix(in srgb, var(--color-accent) 15%, transparent);
+}
+
+.form-group input:disabled {
+  background: var(--color-bg-tertiary);
+  cursor: not-allowed;
 }
 
 .form-group textarea {
@@ -666,9 +679,9 @@ onMounted(() => {
 
 .error-message {
   padding: 12px;
-  background: #fee2e2;
-  color: #991b1b;
-  border-radius: 4px;
+  background: color-mix(in srgb, var(--color-danger) 10%, transparent);
+  color: var(--color-danger);
+  border-radius: var(--radius-sm);
   margin-bottom: 16px;
   font-size: 14px;
 }
@@ -679,15 +692,6 @@ onMounted(() => {
   justify-content: flex-end;
 }
 
-.btn-secondary {
-  background: #6b7280;
-  color: white;
-}
-
-.btn-secondary:hover:not(:disabled) {
-  background: #4b5563;
-}
-
 /* Mobile Cards */
 .bookings-cards {
   display: none;
@@ -705,10 +709,10 @@ onMounted(() => {
   }
 
   .booking-card {
-    border: 1px solid #e5e7eb;
-    border-radius: 8px;
+    border: 1px solid var(--color-border);
+    border-radius: var(--radius-md);
     padding: 16px;
-    background: #fafafa;
+    background: var(--color-bg-secondary);
   }
 
   .booking-header {
@@ -717,13 +721,13 @@ onMounted(() => {
     align-items: start;
     margin-bottom: 12px;
     padding-bottom: 12px;
-    border-bottom: 1px solid #e5e7eb;
+    border-bottom: 1px solid var(--color-border);
   }
 
   .booking-header h3 {
     margin: 0;
     font-size: 16px;
-    color: #374151;
+    color: var(--color-text-primary);
   }
 
   .booking-details {
@@ -737,16 +741,17 @@ onMounted(() => {
     display: flex;
     justify-content: space-between;
     font-size: 14px;
+    color: var(--color-text-primary);
   }
 
   .booking-row .label {
     font-weight: 500;
-    color: #6b7280;
+    color: var(--color-text-secondary);
   }
 
   .booking-actions {
     padding-top: 12px;
-    border-top: 1px solid #e5e7eb;
+    border-top: 1px solid var(--color-border);
   }
 }
 </style>
diff --git a/frontend/src/views/Register.vue b/frontend/src/views/Register.vue
index f5ba373..efd724f 100644
--- a/frontend/src/views/Register.vue
+++ b/frontend/src/views/Register.vue
@@ -145,12 +145,12 @@ const handleRegister = async () => {
 h2 {
   text-align: center;
   margin-bottom: 0.5rem;
-  color: #2c3e50;
+  color: var(--color-text-primary);
 }
 
 .subtitle {
   text-align: center;
-  color: #7f8c8d;
+  color: var(--color-text-secondary);
   margin-bottom: 2rem;
 }
 
@@ -158,7 +158,7 @@ h2 {
   display: block;
   margin-top: 0.25rem;
   font-size: 0.85rem;
-  color: #7f8c8d;
+  color: var(--color-text-secondary);
 }
 
 .btn-block {
@@ -169,11 +169,11 @@ h2 {
 .login-link {
   text-align: center;
   margin-top: 1.5rem;
-  color: #7f8c8d;
+  color: var(--color-text-secondary);
 }
 
 .login-link a {
-  color: #3498db;
+  color: var(--color-accent);
   text-decoration: none;
 }
 
@@ -184,18 +184,18 @@ h2 {
 .error {
   margin-top: 1rem;
   padding: 0.75rem;
-  background: #fee;
-  border-left: 3px solid #e74c3c;
-  border-radius: 4px;
-  color: #c0392b;
+  background: color-mix(in srgb, var(--color-danger) 10%, transparent);
+  border-left: 3px solid var(--color-danger);
+  border-radius: var(--radius-sm);
+  color: var(--color-danger);
 }
 
 .success {
   margin-top: 1rem;
   padding: 0.75rem;
-  background: #d4edda;
-  border-left: 3px solid #28a745;
-  border-radius: 4px;
-  color: #155724;
+  background: color-mix(in srgb, var(--color-success) 10%, transparent);
+  border-left: 3px solid var(--color-success);
+  border-radius: var(--radius-sm);
+  color: var(--color-success);
 }
 </style>
diff --git a/frontend/src/views/Settings.vue b/frontend/src/views/Settings.vue
index c714d6d..b0047cc 100644
--- a/frontend/src/views/Settings.vue
+++ b/frontend/src/views/Settings.vue
@@ -3,9 +3,7 @@
     <h2>Global Booking Settings</h2>
 
     <!-- Settings Form -->
-    <div class="card">
-      <h3>Booking Rules Configuration</h3>
-
+    <CollapsibleSection title="Booking Rules Configuration" :icon="Sliders">
       <div v-if="loadingSettings" class="loading">Loading settings...</div>
 
       <form v-else @submit.prevent="handleSubmit" class="settings-form">
@@ -108,25 +106,26 @@
 
       <div v-if="error" class="error">{{ error }}</div>
       <div v-if="success" class="success">{{ success }}</div>
-    </div>
+    </CollapsibleSection>
 
     <!-- Info Card -->
-    <div class="card info-card">
-      <h4>About These Settings</h4>
-      <ul>
+    <CollapsibleSection title="About These Settings" :icon="Info">
+      <ul class="info-list">
         <li><strong>Duration:</strong> Controls minimum and maximum booking length</li>
         <li><strong>Working Hours:</strong> Bookings outside these hours will be rejected</li>
         <li><strong>Max Bookings:</strong> Limits how many bookings a user can make per day</li>
         <li><strong>Cancel Policy:</strong> Users cannot cancel bookings too close to start time</li>
       </ul>
       <p class="note">These rules apply to all new booking requests.</p>
-    </div>
+    </CollapsibleSection>
   </div>
 </template>
 
 <script setup lang="ts">
 import { ref, onMounted } from 'vue'
 import { settingsApi, handleApiError } from '@/services/api'
+import CollapsibleSection from '@/components/CollapsibleSection.vue'
+import { Sliders, Info } from 'lucide-vue-next'
 import type { Settings } from '@/types'
 
 const loadingSettings = ref(true)
@@ -163,7 +162,6 @@ const loadSettings = async () => {
 }
 
 const validateForm = (): boolean => {
-  // Validate all fields are positive
   if (
     formData.value.min_duration_minutes <= 0 ||
     formData.value.max_duration_minutes <= 0 ||
@@ -176,19 +174,16 @@ const validateForm = (): boolean => {
     return false
   }
 
-  // Validate min < max duration
   if (formData.value.min_duration_minutes >= formData.value.max_duration_minutes) {
     error.value = 'Minimum duration must be less than maximum duration'
     return false
   }
 
-  // Validate working hours start < end
   if (formData.value.working_hours_start >= formData.value.working_hours_end) {
     error.value = 'Working hours start must be less than working hours end'
     return false
   }
 
-  // Validate working hours are within 0-23 for start and 1-24 for end
   if (formData.value.working_hours_start < 0 || formData.value.working_hours_start > 23) {
     error.value = 'Working hours start must be between 0 and 23'
     return false
@@ -206,7 +201,6 @@ const handleSubmit = async () => {
   error.value = ''
   success.value = ''
 
-  // Client-side validation
   if (!validateForm()) {
     return
   }
@@ -239,21 +233,7 @@ onMounted(() => {
 
 h2 {
   margin-bottom: 1.5rem;
-  color: #333;
-}
-
-.card {
-  background: white;
-  border-radius: 8px;
-  padding: 1.5rem;
-  margin-bottom: 1.5rem;
-  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
-}
-
-h3, h4 {
-  margin-top: 0;
-  margin-bottom: 1.5rem;
-  color: #444;
+  color: var(--color-text-primary);
 }
 
 .settings-form {
@@ -276,18 +256,27 @@ h3, h4 {
 
 .form-group label {
   font-weight: 500;
-  color: #555;
+  color: var(--color-text-primary);
+  font-size: 14px;
 }
 
 .form-group input {
   padding: 0.5rem;
-  border: 1px solid #ddd;
-  border-radius: 4px;
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-sm);
   font-size: 1rem;
+  background: var(--color-surface);
+  color: var(--color-text-primary);
+}
+
+.form-group input:focus {
+  outline: none;
+  border-color: var(--color-accent);
+  box-shadow: 0 0 0 3px color-mix(in srgb, var(--color-accent) 15%, transparent);
 }
 
 .form-group small {
-  color: #666;
+  color: var(--color-text-secondary);
   font-size: 0.875rem;
 }
 
@@ -300,19 +289,19 @@ h3, h4 {
 .btn {
   padding: 0.6rem 1.2rem;
   border: none;
-  border-radius: 4px;
+  border-radius: var(--radius-sm);
   font-size: 1rem;
   cursor: pointer;
-  transition: background-color 0.2s;
+  transition: all var(--transition-fast);
 }
 
 .btn-primary {
-  background-color: #4caf50;
+  background: var(--color-accent);
   color: white;
 }
 
 .btn-primary:hover:not(:disabled) {
-  background-color: #45a049;
+  background: var(--color-accent-hover);
 }
 
 .btn:disabled {
@@ -323,46 +312,48 @@ h3, h4 {
 .loading {
   text-align: center;
   padding: 2rem;
-  color: #666;
+  color: var(--color-text-secondary);
 }
 
 .error {
   padding: 0.75rem;
-  background-color: #fee;
-  border: 1px solid #fcc;
-  border-radius: 4px;
-  color: #c33;
+  background: color-mix(in srgb, var(--color-danger) 10%, transparent);
+  border-radius: var(--radius-sm);
+  color: var(--color-danger);
   margin-top: 1rem;
 }
 
 .success {
   padding: 0.75rem;
-  background-color: #efe;
-  border: 1px solid #cfc;
-  border-radius: 4px;
-  color: #3c3;
+  background: color-mix(in srgb, var(--color-success) 10%, transparent);
+  border-radius: var(--radius-sm);
+  color: var(--color-success);
   margin-top: 1rem;
 }
 
-.info-card {
-  background-color: #f8f9fa;
-}
-
-.info-card ul {
+.info-list {
   margin: 0;
   padding-left: 1.5rem;
 }
 
-.info-card li {
+.info-list li {
   margin-bottom: 0.5rem;
-  color: #555;
+  color: var(--color-text-secondary);
+}
+
+.info-list strong {
+  color: var(--color-text-primary);
 }
 
 .note {
   margin-top: 1rem;
   margin-bottom: 0;
   font-style: italic;
-  color: #666;
+  color: var(--color-text-secondary);
+}
+
+.collapsible-section + .collapsible-section {
+  margin-top: 16px;
 }
 
 @media (max-width: 768px) {
diff --git a/frontend/src/views/SpaceDetail.vue b/frontend/src/views/SpaceDetail.vue
index a134015..89225f3 100644
--- a/frontend/src/views/SpaceDetail.vue
+++ b/frontend/src/views/SpaceDetail.vue
@@ -33,14 +33,7 @@
           <div class="space-meta">
             <span class="badge badge-type">{{ formatType(space.type) }}</span>
             <span class="badge badge-capacity">
-              <svg class="icon" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-                <path
-                  stroke-linecap="round"
-                  stroke-linejoin="round"
-                  stroke-width="2"
-                  d="M12 4.354a4 4 0 110 5.292M15 21H3v-1a6 6 0 0112 0v1zm0 0h6v-1a6 6 0 00-9-5.197M13 7a4 4 0 11-8 0 4 4 0 018 0z"
-                />
-              </svg>
+              <Users :size="16" />
               Capacity: {{ space.capacity }}
             </span>
             <span :class="['badge', space.is_active ? 'badge-active' : 'badge-inactive']">
@@ -53,14 +46,7 @@
           :disabled="!space.is_active"
           @click="handleReserve"
         >
-          <svg class="icon" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-            <path
-              stroke-linecap="round"
-              stroke-linejoin="round"
-              stroke-width="2"
-              d="M12 6v6m0 0v6m0-6h6m-6 0H6"
-            />
-          </svg>
+          <Plus :size="18" />
           {{ showBookingForm ? 'Cancel Reservation' : 'Reserve Space' }}
         </button>
       </div>
@@ -99,6 +85,7 @@ import { useRoute } from 'vue-router'
 import { spacesApi, handleApiError } from '@/services/api'
 import SpaceCalendar from '@/components/SpaceCalendar.vue'
 import BookingForm from '@/components/BookingForm.vue'
+import { Users, Plus } from 'lucide-vue-next'
 import type { Space } from '@/types'
 
 const route = useRoute()
@@ -132,7 +119,6 @@ const loadSpace = async () => {
     }
 
     // Fetch all spaces and filter by ID
-    // (Could be optimized with a dedicated GET /api/spaces/:id endpoint in the future)
     const spaces = await spacesApi.list()
     const foundSpace = spaces.find((s) => s.id === spaceId)
 
@@ -170,11 +156,6 @@ onMounted(() => {
 </script>
 
 <style scoped>
-.space-detail {
-  max-width: 1200px;
-  margin: 0 auto;
-}
-
 /* Breadcrumbs */
 .breadcrumbs {
   display: flex;
@@ -182,26 +163,26 @@ onMounted(() => {
   gap: 8px;
   margin-bottom: 24px;
   font-size: 14px;
-  color: #6b7280;
+  color: var(--color-text-secondary);
 }
 
 .breadcrumbs a {
-  color: #3b82f6;
+  color: var(--color-accent);
   text-decoration: none;
-  transition: color 0.2s;
+  transition: color var(--transition-fast);
 }
 
 .breadcrumbs a:hover {
-  color: #2563eb;
+  color: var(--color-accent-hover);
   text-decoration: underline;
 }
 
 .breadcrumbs .separator {
-  color: #9ca3af;
+  color: var(--color-text-muted);
 }
 
 .breadcrumbs .current {
-  color: #374151;
+  color: var(--color-text-primary);
   font-weight: 500;
 }
 
@@ -212,14 +193,14 @@ onMounted(() => {
   align-items: center;
   justify-content: center;
   padding: 80px 20px;
-  color: #6b7280;
+  color: var(--color-text-secondary);
 }
 
 .spinner {
   width: 48px;
   height: 48px;
-  border: 4px solid #e5e7eb;
-  border-top-color: #3b82f6;
+  border: 4px solid var(--color-border);
+  border-top-color: var(--color-accent);
   border-radius: 50%;
   animation: spin 0.8s linear infinite;
   margin-bottom: 16px;
@@ -239,21 +220,22 @@ onMounted(() => {
 }
 
 .error-card {
-  background: white;
-  border-radius: 8px;
+  background: var(--color-surface);
+  border-radius: var(--radius-md);
   padding: 40px;
-  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
+  box-shadow: var(--shadow-sm);
+  border: 1px solid var(--color-border);
   text-align: center;
   max-width: 500px;
 }
 
 .error-card h3 {
-  color: #991b1b;
+  color: var(--color-danger);
   margin-bottom: 12px;
 }
 
 .error-card p {
-  color: #6b7280;
+  color: var(--color-text-secondary);
   margin-bottom: 24px;
 }
 
@@ -281,7 +263,7 @@ onMounted(() => {
 .header-info h1 {
   font-size: 32px;
   font-weight: 700;
-  color: #111827;
+  color: var(--color-text-primary);
   margin-bottom: 16px;
 }
 
@@ -303,42 +285,37 @@ onMounted(() => {
 }
 
 .badge-type {
-  background: #dbeafe;
-  color: #1e40af;
+  background: var(--color-accent-light);
+  color: var(--color-accent);
 }
 
 .badge-capacity {
-  background: #f3f4f6;
-  color: #374151;
+  background: var(--color-bg-tertiary);
+  color: var(--color-text-primary);
 }
 
 .badge-active {
-  background: #d1fae5;
-  color: #065f46;
+  background: color-mix(in srgb, var(--color-success) 15%, transparent);
+  color: var(--color-success);
 }
 
 .badge-inactive {
-  background: #fee2e2;
-  color: #991b1b;
+  background: color-mix(in srgb, var(--color-danger) 15%, transparent);
+  color: var(--color-danger);
 }
 
-.icon {
-  width: 18px;
-  height: 18px;
-}
-
-/* Reserve Button */
+/* Buttons */
 .btn {
   display: inline-flex;
   align-items: center;
   gap: 8px;
   padding: 12px 24px;
   border: none;
-  border-radius: 8px;
+  border-radius: var(--radius-md);
   font-size: 16px;
   font-weight: 600;
   cursor: pointer;
-  transition: all 0.2s;
+  transition: all var(--transition-fast);
   white-space: nowrap;
 }
 
@@ -348,14 +325,14 @@ onMounted(() => {
 }
 
 .btn-primary {
-  background: #3b82f6;
+  background: var(--color-accent);
   color: white;
 }
 
 .btn-primary:hover:not(:disabled) {
-  background: #2563eb;
+  background: var(--color-accent-hover);
   transform: translateY(-1px);
-  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
+  box-shadow: var(--shadow-md);
 }
 
 .btn-reserve {
@@ -365,33 +342,29 @@ onMounted(() => {
 
 /* Cards */
 .card {
-  background: white;
-  border-radius: 8px;
+  background: var(--color-surface);
+  border-radius: var(--radius-md);
   padding: 24px;
-  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
+  box-shadow: var(--shadow-sm);
+  border: 1px solid var(--color-border);
 }
 
 .card h3 {
   font-size: 20px;
   font-weight: 600;
-  color: #111827;
+  color: var(--color-text-primary);
   margin-bottom: 12px;
 }
 
 /* Description Card */
 .description-card p {
-  color: #4b5563;
+  color: var(--color-text-secondary);
   line-height: 1.6;
 }
 
-/* Booking Card */
-.booking-card h3 {
-  margin-bottom: 16px;
-}
-
 /* Calendar Card */
 .calendar-subtitle {
-  color: #6b7280;
+  color: var(--color-text-secondary);
   font-size: 14px;
   margin-bottom: 20px;
 }
@@ -411,14 +384,14 @@ onMounted(() => {
 }
 
 .modal-content {
-  background: white;
-  border-radius: 8px;
+  background: var(--color-surface);
+  border-radius: var(--radius-md);
   padding: 24px;
   max-width: 600px;
   width: 90%;
   max-height: 90vh;
   overflow-y: auto;
-  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
+  box-shadow: var(--shadow-lg);
 }
 
 .modal-content h3 {
diff --git a/frontend/src/views/Spaces.vue b/frontend/src/views/Spaces.vue
index 255bb11..4908645 100644
--- a/frontend/src/views/Spaces.vue
+++ b/frontend/src/views/Spaces.vue
@@ -42,14 +42,7 @@
 
     <!-- Empty State -->
     <div v-else-if="filteredSpaces.length === 0" class="empty-state">
-      <svg class="empty-icon" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-        <path
-          stroke-linecap="round"
-          stroke-linejoin="round"
-          stroke-width="2"
-          d="M19 21V5a2 2 0 00-2-2H7a2 2 0 00-2 2v16m14 0h2m-2 0h-5m-9 0H3m2 0h5M9 7h1m-1 4h1m4-4h1m-1 4h1m-5 10v-5a1 1 0 011-1h2a1 1 0 011 1v5m-4 0h4"
-        />
-      </svg>
+      <Building2 :size="80" class="empty-icon" />
       <h3>No Spaces Found</h3>
       <p>{{ selectedType || selectedStatus ? 'Try adjusting your filters' : 'No spaces are currently available' }}</p>
     </div>
@@ -72,27 +65,13 @@
         <div class="space-card-body">
           <div class="space-info">
             <div class="info-item">
-              <svg class="icon" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-                <path
-                  stroke-linecap="round"
-                  stroke-linejoin="round"
-                  stroke-width="2"
-                  d="M7 7h.01M7 3h5c.512 0 1.024.195 1.414.586l7 7a2 2 0 010 2.828l-7 7a2 2 0 01-2.828 0l-7-7A1.994 1.994 0 013 12V7a4 4 0 014-4z"
-                />
-              </svg>
+              <Tag :size="18" class="info-icon" />
               <span class="label">Type:</span>
               <span class="value">{{ formatType(space.type) }}</span>
             </div>
 
             <div class="info-item">
-              <svg class="icon" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-                <path
-                  stroke-linecap="round"
-                  stroke-linejoin="round"
-                  stroke-width="2"
-                  d="M12 4.354a4 4 0 110 5.292M15 21H3v-1a6 6 0 0112 0v1zm0 0h6v-1a6 6 0 00-9-5.197M13 7a4 4 0 11-8 0 4 4 0 018 0z"
-                />
-              </svg>
+              <Users :size="18" class="info-icon" />
               <span class="label">Capacity:</span>
               <span class="value">{{ space.capacity }} {{ space.capacity === 1 ? 'person' : 'people' }}</span>
             </div>
@@ -106,14 +85,7 @@
         <div class="space-card-footer">
           <button class="btn btn-secondary">
             View Details
-            <svg class="icon-small" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-              <path
-                stroke-linecap="round"
-                stroke-linejoin="round"
-                stroke-width="2"
-                d="M9 5l7 7-7 7"
-              />
-            </svg>
+            <ChevronRight :size="16" />
           </button>
         </div>
       </div>
@@ -125,6 +97,7 @@
 import { ref, computed, onMounted } from 'vue'
 import { useRouter } from 'vue-router'
 import { spacesApi, handleApiError } from '@/services/api'
+import { Building2, Tag, Users, ChevronRight } from 'lucide-vue-next'
 import type { Space } from '@/types'
 
 const router = useRouter()
@@ -194,11 +167,6 @@ onMounted(() => {
 </script>
 
 <style scoped>
-.spaces {
-  max-width: 1400px;
-  margin: 0 auto;
-}
-
 /* Header */
 .spaces-header {
   display: flex;
@@ -210,12 +178,12 @@ onMounted(() => {
 .spaces-header h2 {
   font-size: 32px;
   font-weight: 700;
-  color: #111827;
+  color: var(--color-text-primary);
   margin-bottom: 8px;
 }
 
 .subtitle {
-  color: #6b7280;
+  color: var(--color-text-secondary);
   font-size: 16px;
 }
 
@@ -236,28 +204,27 @@ onMounted(() => {
 .filter-group label {
   font-size: 14px;
   font-weight: 500;
-  color: #374151;
+  color: var(--color-text-primary);
 }
 
 .filter-select {
   padding: 8px 12px;
-  border: 1px solid #d1d5db;
-  border-radius: 6px;
-  background: white;
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-sm);
+  background: var(--color-surface);
   font-size: 14px;
-  color: #374151;
+  color: var(--color-text-primary);
   cursor: pointer;
-  transition: border-color 0.2s;
+  transition: border-color var(--transition-fast);
 }
 
 .filter-select:hover {
-  border-color: #9ca3af;
+  border-color: var(--color-text-muted);
 }
 
 .filter-select:focus {
   outline: none;
-  border-color: #3b82f6;
-  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
+  border-color: var(--color-accent);
 }
 
 /* Loading State */
@@ -267,14 +234,14 @@ onMounted(() => {
   align-items: center;
   justify-content: center;
   padding: 80px 20px;
-  color: #6b7280;
+  color: var(--color-text-secondary);
 }
 
 .spinner {
   width: 48px;
   height: 48px;
-  border: 4px solid #e5e7eb;
-  border-top-color: #3b82f6;
+  border: 4px solid var(--color-border);
+  border-top-color: var(--color-accent);
   border-radius: 50%;
   animation: spin 0.8s linear infinite;
   margin-bottom: 16px;
@@ -288,22 +255,23 @@ onMounted(() => {
 
 /* Error State */
 .error-card {
-  background: white;
-  border-radius: 8px;
+  background: var(--color-surface);
+  border-radius: var(--radius-md);
   padding: 40px;
-  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
+  box-shadow: var(--shadow-sm);
+  border: 1px solid var(--color-border);
   text-align: center;
   max-width: 500px;
   margin: 40px auto;
 }
 
 .error-card h3 {
-  color: #991b1b;
+  color: var(--color-danger);
   margin-bottom: 12px;
 }
 
 .error-card p {
-  color: #6b7280;
+  color: var(--color-text-secondary);
   margin-bottom: 24px;
 }
 
@@ -314,21 +282,20 @@ onMounted(() => {
 }
 
 .empty-icon {
-  width: 80px;
-  height: 80px;
-  color: #d1d5db;
+  color: var(--color-border);
   margin: 0 auto 24px;
+  display: block;
 }
 
 .empty-state h3 {
   font-size: 20px;
   font-weight: 600;
-  color: #374151;
+  color: var(--color-text-primary);
   margin-bottom: 8px;
 }
 
 .empty-state p {
-  color: #6b7280;
+  color: var(--color-text-secondary);
   font-size: 16px;
 }
 
@@ -341,19 +308,20 @@ onMounted(() => {
 
 /* Space Card */
 .space-card {
-  background: white;
-  border-radius: 8px;
+  background: var(--color-surface);
+  border-radius: var(--radius-md);
   padding: 24px;
-  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
+  box-shadow: var(--shadow-sm);
+  border: 1px solid var(--color-border);
   cursor: pointer;
-  transition: all 0.2s;
+  transition: all var(--transition-fast);
   display: flex;
   flex-direction: column;
 }
 
 .space-card:hover {
   transform: translateY(-4px);
-  box-shadow: 0 8px 16px rgba(0, 0, 0, 0.15);
+  box-shadow: var(--shadow-lg);
 }
 
 .space-card-header {
@@ -367,7 +335,7 @@ onMounted(() => {
 .space-card-header h3 {
   font-size: 20px;
   font-weight: 600;
-  color: #111827;
+  color: var(--color-text-primary);
   flex: 1;
 }
 
@@ -375,20 +343,20 @@ onMounted(() => {
   display: inline-flex;
   align-items: center;
   padding: 4px 12px;
-  border-radius: 12px;
+  border-radius: var(--radius-lg);
   font-size: 12px;
   font-weight: 500;
   white-space: nowrap;
 }
 
 .badge-active {
-  background: #d1fae5;
-  color: #065f46;
+  background: color-mix(in srgb, var(--color-success) 15%, transparent);
+  color: var(--color-success);
 }
 
 .badge-inactive {
-  background: #fee2e2;
-  color: #991b1b;
+  background: color-mix(in srgb, var(--color-danger) 15%, transparent);
+  color: var(--color-danger);
 }
 
 .space-card-body {
@@ -408,27 +376,25 @@ onMounted(() => {
   align-items: center;
   gap: 8px;
   font-size: 14px;
-  color: #4b5563;
+  color: var(--color-text-secondary);
 }
 
-.icon {
-  width: 18px;
-  height: 18px;
-  color: #9ca3af;
+.info-icon {
+  color: var(--color-text-muted);
   flex-shrink: 0;
 }
 
 .label {
   font-weight: 500;
-  color: #6b7280;
+  color: var(--color-text-secondary);
 }
 
 .value {
-  color: #374151;
+  color: var(--color-text-primary);
 }
 
 .space-description {
-  color: #6b7280;
+  color: var(--color-text-secondary);
   font-size: 14px;
   line-height: 1.5;
   margin-top: 12px;
@@ -446,34 +412,29 @@ onMounted(() => {
   gap: 8px;
   padding: 10px 20px;
   border: none;
-  border-radius: 6px;
+  border-radius: var(--radius-sm);
   font-size: 14px;
   font-weight: 600;
   cursor: pointer;
-  transition: all 0.2s;
+  transition: all var(--transition-fast);
 }
 
 .btn-primary {
-  background: #3b82f6;
+  background: var(--color-accent);
   color: white;
 }
 
 .btn-primary:hover {
-  background: #2563eb;
+  background: var(--color-accent-hover);
 }
 
 .btn-secondary {
-  background: #f3f4f6;
-  color: #374151;
+  background: var(--color-bg-secondary);
+  color: var(--color-text-primary);
 }
 
 .btn-secondary:hover {
-  background: #e5e7eb;
-}
-
-.icon-small {
-  width: 16px;
-  height: 16px;
+  background: var(--color-bg-tertiary);
 }
 
 /* Responsive */
diff --git a/frontend/src/views/UserProfile.vue b/frontend/src/views/UserProfile.vue
index 40539a9..415c934 100644
--- a/frontend/src/views/UserProfile.vue
+++ b/frontend/src/views/UserProfile.vue
@@ -3,8 +3,7 @@
     <h2>User Profile</h2>
 
     <!-- Profile Information Card -->
-    <div class="card">
-      <h3>Profile Information</h3>
+    <CollapsibleSection title="Profile Information" :icon="UserIcon">
       <div v-if="user" class="profile-info">
         <div class="info-item">
           <label>Email:</label>
@@ -23,12 +22,10 @@
           <span>{{ user.role }}</span>
         </div>
       </div>
-    </div>
+    </CollapsibleSection>
 
     <!-- Timezone Preferences Card -->
-    <div class="card">
-      <h3>Timezone Preferences</h3>
-
+    <CollapsibleSection title="Timezone Preferences" :icon="Globe">
       <div v-if="loadingTimezones" class="loading">Loading timezones...</div>
 
       <div v-else class="timezone-settings">
@@ -56,18 +53,16 @@
         <div v-if="timezoneSuccess" class="success">{{ timezoneSuccess }}</div>
         <div v-if="timezoneError" class="error">{{ timezoneError }}</div>
       </div>
-    </div>
+    </CollapsibleSection>
 
     <!-- Google Calendar Integration Card -->
-    <div class="card">
-      <h3>Google Calendar Integration</h3>
-
+    <CollapsibleSection title="Google Calendar Integration" :icon="CalendarDays">
       <div v-if="loadingGoogleStatus" class="loading">Checking connection status...</div>
 
       <div v-else>
         <div v-if="googleStatus.connected" class="google-connected">
           <div class="status-indicator">
-            <span class="status-icon">✓</span>
+            <CheckCircle :size="20" class="status-icon-connected" />
             <span>Connected to Google Calendar</span>
           </div>
 
@@ -103,12 +98,11 @@
 
       <div v-if="error" class="error">{{ error }}</div>
       <div v-if="success" class="success">{{ success }}</div>
-    </div>
+    </CollapsibleSection>
 
     <!-- Info Card -->
-    <div class="card info-card">
-      <h4>About Calendar Integration</h4>
-      <ul>
+    <CollapsibleSection title="About Calendar Integration" :icon="Info">
+      <ul class="info-list">
         <li>
           <strong>Automatic Sync:</strong> When your booking is approved, it's automatically added to
           your Google Calendar
@@ -122,7 +116,7 @@
           above
         </li>
       </ul>
-    </div>
+    </CollapsibleSection>
   </div>
 </template>
 
@@ -131,6 +125,8 @@ import { ref, computed, onMounted } from 'vue'
 import { usersApi, googleCalendarApi, handleApiError } from '@/services/api'
 import { useAuthStore } from '@/stores/auth'
 import { formatDateTime as formatDateTimeUtil } from '@/utils/datetime'
+import CollapsibleSection from '@/components/CollapsibleSection.vue'
+import { User as UserIcon, Globe, CalendarDays, CheckCircle, Info } from 'lucide-vue-next'
 import type { User } from '@/types'
 
 const authStore = useAuthStore()
@@ -184,7 +180,6 @@ const updateTimezone = async () => {
   try {
     await usersApi.updateTimezone(selectedTimezone.value)
 
-    // Update auth store
     if (authStore.user) {
       authStore.user.timezone = selectedTimezone.value
     }
@@ -195,7 +190,6 @@ const updateTimezone = async () => {
     }, 5000)
   } catch (err) {
     timezoneError.value = handleApiError(err)
-    // Revert selection on error
     if (user.value) {
       selectedTimezone.value = user.value.timezone
     }
@@ -223,21 +217,17 @@ const connectGoogle = async () => {
   try {
     const response = await googleCalendarApi.connect()
 
-    // Open OAuth URL in popup window
     const popup = window.open(
       response.authorization_url,
       'Google Calendar Authorization',
       'width=600,height=600,toolbar=no,menubar=no,location=no'
     )
 
-    // Poll for connection status
     const pollInterval = setInterval(async () => {
-      // Check if popup was closed
       if (popup && popup.closed) {
         clearInterval(pollInterval)
         connecting.value = false
 
-        // Check status one more time
         await checkGoogleStatus()
 
         if (googleStatus.value.connected) {
@@ -247,7 +237,6 @@ const connectGoogle = async () => {
           }, 3000)
         }
       } else {
-        // Poll for connection status
         try {
           const status = await googleCalendarApi.status()
           if (status.connected) {
@@ -256,7 +245,6 @@ const connectGoogle = async () => {
             googleStatus.value = status
             success.value = 'Google Calendar connected successfully!'
 
-            // Close popup
             if (popup) {
               popup.close()
             }
@@ -271,7 +259,6 @@ const connectGoogle = async () => {
       }
     }, 2000)
 
-    // Stop polling after 5 minutes
     setTimeout(() => {
       clearInterval(pollInterval)
       connecting.value = false
@@ -328,22 +315,7 @@ onMounted(() => {
 
 h2 {
   margin-bottom: 1.5rem;
-  color: #333;
-}
-
-.card {
-  background: white;
-  border-radius: 8px;
-  padding: 1.5rem;
-  margin-bottom: 1.5rem;
-  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
-}
-
-h3,
-h4 {
-  margin-top: 0;
-  margin-bottom: 1.5rem;
-  color: #444;
+  color: var(--color-text-primary);
 }
 
 .profile-info {
@@ -360,17 +332,17 @@ h4 {
 .info-item label {
   font-weight: 600;
   min-width: 120px;
-  color: #555;
+  color: var(--color-text-secondary);
 }
 
 .info-item span {
-  color: #333;
+  color: var(--color-text-primary);
 }
 
 .loading {
   text-align: center;
   padding: 2rem;
-  color: #666;
+  color: var(--color-text-secondary);
 }
 
 .google-connected,
@@ -386,29 +358,21 @@ h4 {
   gap: 0.5rem;
   font-size: 1.1rem;
   font-weight: 500;
-  color: #4caf50;
+  color: var(--color-success);
 }
 
-.status-icon {
-  display: inline-flex;
-  align-items: center;
-  justify-content: center;
-  width: 24px;
-  height: 24px;
-  background-color: #4caf50;
-  color: white;
-  border-radius: 50%;
-  font-size: 0.9rem;
+.status-icon-connected {
+  color: var(--color-success);
 }
 
 .expiry-info {
-  color: #666;
+  color: var(--color-text-secondary);
   font-size: 0.9rem;
   margin: 0;
 }
 
 .info-text {
-  color: #555;
+  color: var(--color-text-secondary);
   line-height: 1.6;
   margin: 0;
 }
@@ -420,35 +384,35 @@ h4 {
 
 .benefits-list li {
   margin-bottom: 0.5rem;
-  color: #555;
+  color: var(--color-text-secondary);
 }
 
 .btn {
   padding: 0.6rem 1.2rem;
   border: none;
-  border-radius: 4px;
+  border-radius: var(--radius-sm);
   font-size: 1rem;
   cursor: pointer;
-  transition: background-color 0.2s;
+  transition: all var(--transition-fast);
   align-self: flex-start;
 }
 
 .btn-primary {
-  background-color: #4285f4;
+  background: var(--color-accent);
   color: white;
 }
 
 .btn-primary:hover:not(:disabled) {
-  background-color: #357ae8;
+  background: var(--color-accent-hover);
 }
 
 .btn-danger {
-  background-color: #dc3545;
+  background: var(--color-danger);
   color: white;
 }
 
 .btn-danger:hover:not(:disabled) {
-  background-color: #c82333;
+  background: color-mix(in srgb, var(--color-danger) 85%, black);
 }
 
 .btn:disabled {
@@ -458,34 +422,32 @@ h4 {
 
 .error {
   padding: 0.75rem;
-  background-color: #fee;
-  border: 1px solid #fcc;
-  border-radius: 4px;
-  color: #c33;
+  background: color-mix(in srgb, var(--color-danger) 10%, transparent);
+  border-radius: var(--radius-sm);
+  color: var(--color-danger);
   margin-top: 1rem;
 }
 
 .success {
   padding: 0.75rem;
-  background-color: #efe;
-  border: 1px solid #cfc;
-  border-radius: 4px;
-  color: #3c3;
+  background: color-mix(in srgb, var(--color-success) 10%, transparent);
+  border-radius: var(--radius-sm);
+  color: var(--color-success);
   margin-top: 1rem;
 }
 
-.info-card {
-  background-color: #f8f9fa;
-}
-
-.info-card ul {
+.info-list {
   margin: 0;
   padding-left: 1.5rem;
 }
 
-.info-card li {
+.info-list li {
   margin-bottom: 0.5rem;
-  color: #555;
+  color: var(--color-text-secondary);
+}
+
+.info-list strong {
+  color: var(--color-text-primary);
 }
 
 .timezone-settings {
@@ -502,16 +464,18 @@ h4 {
 
 .form-group label {
   font-weight: 600;
-  color: #555;
+  color: var(--color-text-secondary);
 }
 
 .timezone-select {
   padding: 0.5rem;
-  border: 1px solid #ddd;
-  border-radius: 4px;
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-sm);
   font-size: 1rem;
   max-width: 400px;
   cursor: pointer;
+  background: var(--color-surface);
+  color: var(--color-text-primary);
 }
 
 .timezone-select:disabled {
@@ -520,9 +484,13 @@ h4 {
 }
 
 .help-text {
-  color: #666;
+  color: var(--color-text-secondary);
   font-size: 0.9rem;
   font-style: italic;
   margin: 0;
 }
+
+.collapsible-section + .collapsible-section {
+  margin-top: 16px;
+}
 </style>
diff --git a/frontend/src/views/Users.vue b/frontend/src/views/Users.vue
index 34cf233..d6a675b 100644
--- a/frontend/src/views/Users.vue
+++ b/frontend/src/views/Users.vue
@@ -3,13 +3,13 @@
     <div class="page-header">
       <h2>Admin Dashboard - User Management</h2>
       <button class="btn btn-primary" @click="openCreateModal">
+        <UserPlus :size="16" />
         Create New User
       </button>
     </div>
 
     <!-- Filters -->
-    <div class="card">
-      <h3>Filters</h3>
+    <CollapsibleSection title="Filters" :icon="Filter">
       <div class="filters">
         <div class="form-group">
           <label for="filter-role">Filter by Role</label>
@@ -31,68 +31,69 @@
           />
         </div>
       </div>
-    </div>
+    </CollapsibleSection>
 
     <!-- Users List -->
-    <div class="card">
-      <h3>All Users</h3>
+    <CollapsibleSection title="All Users" :icon="UsersIcon">
       <div v-if="loadingUsers" class="loading">Loading users...</div>
       <div v-else-if="users.length === 0" class="empty">
         No users found. {{ filterRole || filterOrganization ? 'Try different filters.' : 'Create one above!' }}
       </div>
-      <table v-else class="users-table">
-        <thead>
-          <tr>
-            <th>Email</th>
-            <th>Full Name</th>
-            <th>Role</th>
-            <th>Organization</th>
-            <th>Status</th>
-            <th>Actions</th>
-          </tr>
-        </thead>
-        <tbody>
-          <tr v-for="user in users" :key="user.id">
-            <td>{{ user.email }}</td>
-            <td>{{ user.full_name }}</td>
-            <td>
-              <span :class="['badge', user.role === 'admin' ? 'badge-admin' : 'badge-user']">
-                {{ user.role }}
-              </span>
-            </td>
-            <td>{{ user.organization || '-' }}</td>
-            <td>
-              <span :class="['badge', user.is_active ? 'badge-active' : 'badge-inactive']">
-                {{ user.is_active ? 'Active' : 'Inactive' }}
-              </span>
-            </td>
-            <td class="actions">
-              <button
-                class="btn btn-sm btn-secondary"
-                @click="startEdit(user)"
-                :disabled="loading"
-              >
-                Edit
-              </button>
-              <button
-                :class="['btn', 'btn-sm', user.is_active ? 'btn-warning' : 'btn-success']"
-                @click="toggleStatus(user)"
-                :disabled="loading"
-              >
-                {{ user.is_active ? 'Deactivate' : 'Activate' }}
-              </button>
-              <button
-                class="btn btn-sm btn-danger"
-                @click="showResetPassword(user)"
-                :disabled="loading"
-              >
-                Reset Password
-              </button>
-            </td>
-          </tr>
-        </tbody>
-      </table>
-    </div>
+      <div v-else class="table-responsive">
+        <table class="data-table">
+          <thead>
+            <tr>
+              <th>Email</th>
+              <th>Full Name</th>
+              <th>Role</th>
+              <th>Organization</th>
+              <th>Status</th>
+              <th>Actions</th>
+            </tr>
+          </thead>
+          <tbody>
+            <tr v-for="user in users" :key="user.id">
+              <td>{{ user.email }}</td>
+              <td>{{ user.full_name }}</td>
+              <td>
+                <span :class="['badge', user.role === 'admin' ? 'badge-admin' : 'badge-user']">
+                  {{ user.role }}
+                </span>
+              </td>
+              <td>{{ user.organization || '-' }}</td>
+              <td>
+                <span :class="['badge', user.is_active ? 'badge-active' : 'badge-inactive']">
+                  {{ user.is_active ? 'Active' : 'Inactive' }}
+                </span>
+              </td>
+              <td class="actions">
+                <button
+                  class="btn btn-sm btn-secondary"
+                  @click="startEdit(user)"
+                  :disabled="loading"
+                >
+                  Edit
+                </button>
+                <button
+                  :class="['btn', 'btn-sm', user.is_active ? 'btn-warning' : 'btn-success']"
+                  @click="toggleStatus(user)"
+                  :disabled="loading"
+                >
+                  {{ user.is_active ? 'Deactivate' : 'Activate' }}
+                </button>
+                <button
+                  class="btn btn-sm btn-danger"
+                  @click="showResetPassword(user)"
+                  :disabled="loading"
+                >
+                  Reset Password
+                </button>
+              </td>
+            </tr>
+          </tbody>
+        </table>
+      </div>
+    </CollapsibleSection>
 
     <!-- Create/Edit User Modal -->
     <div v-if="showFormModal" class="modal" @click.self="closeFormModal">
@@ -200,6 +201,8 @@
 <script setup lang="ts">
 import { ref, onMounted } from 'vue'
 import { usersApi, handleApiError } from '@/services/api'
+import CollapsibleSection from '@/components/CollapsibleSection.vue'
+import { Users as UsersIcon, UserPlus, Filter } from 'lucide-vue-next'
 import type { User } from '@/types'
 
 const users = ref<User[]>([])
@@ -367,11 +370,6 @@ onMounted(() => {
 </script>
 
 <style scoped>
-.users {
-  max-width: 1400px;
-  margin: 0 auto;
-}
-
 .page-header {
   display: flex;
   justify-content: space-between;
@@ -383,20 +381,7 @@ onMounted(() => {
 
 .page-header h2 {
   margin: 0;
-}
-
-.card {
-  background: white;
-  border-radius: 8px;
-  padding: 24px;
-  margin-bottom: 24px;
-  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
-}
-
-.user-form {
-  display: flex;
-  flex-direction: column;
-  gap: 16px;
+  color: var(--color-text-primary);
 }
 
 .filters {
@@ -405,6 +390,12 @@ onMounted(() => {
   gap: 16px;
 }
 
+.user-form {
+  display: flex;
+  flex-direction: column;
+  gap: 16px;
+}
+
 .form-group {
   display: flex;
   flex-direction: column;
@@ -413,28 +404,31 @@ onMounted(() => {
 
 .form-group label {
   font-weight: 500;
-  color: #374151;
+  color: var(--color-text-primary);
+  font-size: 14px;
 }
 
 .form-group input,
 .form-group select,
 .form-group textarea {
   padding: 8px 12px;
-  border: 1px solid #d1d5db;
-  border-radius: 4px;
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-sm);
   font-size: 14px;
+  background: var(--color-surface);
+  color: var(--color-text-primary);
 }
 
 .form-group input:focus,
 .form-group select:focus,
 .form-group textarea:focus {
   outline: none;
-  border-color: #3b82f6;
-  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
+  border-color: var(--color-accent);
+  box-shadow: 0 0 0 3px color-mix(in srgb, var(--color-accent) 15%, transparent);
 }
 
 .form-group input:disabled {
-  background: #f3f4f6;
+  background: var(--color-bg-tertiary);
   cursor: not-allowed;
 }
 
@@ -445,13 +439,16 @@ onMounted(() => {
 }
 
 .btn {
+  display: inline-flex;
+  align-items: center;
+  gap: 6px;
   padding: 10px 20px;
   border: none;
-  border-radius: 4px;
+  border-radius: var(--radius-sm);
   font-size: 14px;
   font-weight: 500;
   cursor: pointer;
-  transition: all 0.2s;
+  transition: all var(--transition-fast);
 }
 
 .btn:disabled {
@@ -460,48 +457,48 @@ onMounted(() => {
 }
 
 .btn-primary {
-  background: #3b82f6;
+  background: var(--color-accent);
   color: white;
 }
 
 .btn-primary:hover:not(:disabled) {
-  background: #2563eb;
+  background: var(--color-accent-hover);
 }
 
 .btn-secondary {
-  background: #6b7280;
-  color: white;
+  background: var(--color-bg-tertiary);
+  color: var(--color-text-primary);
 }
 
 .btn-secondary:hover:not(:disabled) {
-  background: #4b5563;
+  background: var(--color-border);
 }
 
 .btn-success {
-  background: #10b981;
+  background: var(--color-success);
   color: white;
 }
 
 .btn-success:hover:not(:disabled) {
-  background: #059669;
+  background: color-mix(in srgb, var(--color-success) 85%, black);
 }
 
 .btn-warning {
-  background: #f59e0b;
+  background: var(--color-warning);
   color: white;
 }
 
 .btn-warning:hover:not(:disabled) {
-  background: #d97706;
+  background: color-mix(in srgb, var(--color-warning) 85%, black);
 }
 
 .btn-danger {
-  background: #ef4444;
+  background: var(--color-danger);
   color: white;
 }
 
 .btn-danger:hover:not(:disabled) {
-  background: #dc2626;
+  background: color-mix(in srgb, var(--color-danger) 85%, black);
 }
 
 .btn-sm {
@@ -511,53 +508,58 @@ onMounted(() => {
 
 .error {
   padding: 12px;
-  background: #fee2e2;
-  color: #991b1b;
-  border-radius: 4px;
+  background: color-mix(in srgb, var(--color-danger) 10%, transparent);
+  color: var(--color-danger);
+  border-radius: var(--radius-sm);
   margin-top: 12px;
 }
 
 .success {
   padding: 12px;
-  background: #d1fae5;
-  color: #065f46;
-  border-radius: 4px;
+  background: color-mix(in srgb, var(--color-success) 10%, transparent);
+  color: var(--color-success);
+  border-radius: var(--radius-sm);
   margin-top: 12px;
 }
 
 .loading {
   text-align: center;
-  color: #6b7280;
+  color: var(--color-text-secondary);
   padding: 24px;
 }
 
 .empty {
   text-align: center;
-  color: #9ca3af;
+  color: var(--color-text-muted);
   padding: 24px;
 }
 
-.users-table {
+.table-responsive {
+  overflow-x: auto;
+}
+
+.data-table {
   width: 100%;
   border-collapse: collapse;
 }
 
-.users-table th {
+.data-table th {
   text-align: left;
   padding: 12px;
-  background: #f9fafb;
+  background: var(--color-bg-secondary);
   font-weight: 600;
-  color: #374151;
-  border-bottom: 2px solid #e5e7eb;
+  color: var(--color-text-primary);
+  border-bottom: 2px solid var(--color-border);
 }
 
-.users-table td {
+.data-table td {
   padding: 12px;
-  border-bottom: 1px solid #e5e7eb;
+  border-bottom: 1px solid var(--color-border);
+  color: var(--color-text-primary);
 }
 
-.users-table tr:hover {
-  background: #f9fafb;
+.data-table tr:hover {
+  background: var(--color-surface-hover);
 }
 
 .badge {
@@ -569,23 +571,23 @@ onMounted(() => {
 }
 
 .badge-active {
-  background: #d1fae5;
-  color: #065f46;
+  background: color-mix(in srgb, var(--color-success) 15%, transparent);
+  color: var(--color-success);
 }
 
 .badge-inactive {
-  background: #fee2e2;
-  color: #991b1b;
+  background: color-mix(in srgb, var(--color-danger) 15%, transparent);
+  color: var(--color-danger);
 }
 
 .badge-admin {
-  background: #dbeafe;
-  color: #1e40af;
+  background: color-mix(in srgb, var(--color-accent) 15%, transparent);
+  color: var(--color-accent);
 }
 
 .badge-user {
-  background: #f3f4f6;
-  color: #374151;
+  background: var(--color-bg-tertiary);
+  color: var(--color-text-primary);
 }
 
 .actions {
@@ -608,15 +610,31 @@ onMounted(() => {
 }
 
 .modal-content {
-  background: white;
-  border-radius: 8px;
+  background: var(--color-surface);
+  border-radius: var(--radius-md);
   padding: 24px;
   max-width: 500px;
   width: 90%;
-  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
+  box-shadow: var(--shadow-lg);
 }
 
 .modal-content h3 {
   margin-bottom: 16px;
+  color: var(--color-text-primary);
+}
+
+.collapsible-section + .collapsible-section {
+  margin-top: 16px;
+}
+
+@media (max-width: 768px) {
+  .page-header {
+    flex-direction: column;
+    align-items: stretch;
+  }
+
+  .actions {
+    flex-direction: column;
+  }
 }
 </style>
diff --git a/frontend/src/views/VerifyEmail.vue b/frontend/src/views/VerifyEmail.vue
index ac6def8..d85487a 100644
--- a/frontend/src/views/VerifyEmail.vue
+++ b/frontend/src/views/VerifyEmail.vue
@@ -129,8 +129,8 @@ const resendVerification = async () => {
 .spinner {
   width: 50px;
   height: 50px;
-  border: 4px solid #f3f3f3;
-  border-top: 4px solid #3498db;
+  border: 4px solid var(--color-border);
+  border-top: 4px solid var(--color-accent);
   border-radius: 50%;
   animation: spin 1s linear infinite;
   margin: 0 auto 1.5rem;
@@ -153,7 +153,7 @@ const resendVerification = async () => {
 .icon-success {
   width: 80px;
   height: 80px;
-  background: #28a745;
+  background: var(--color-success);
   color: white;
   font-size: 3rem;
   line-height: 80px;
@@ -164,7 +164,7 @@ const resendVerification = async () => {
 .icon-error {
   width: 80px;
   height: 80px;
-  background: #e74c3c;
+  background: var(--color-danger);
   color: white;
   font-size: 3rem;
   line-height: 80px;
@@ -173,17 +173,17 @@ const resendVerification = async () => {
 }
 
 h2 {
-  color: #2c3e50;
+  color: var(--color-text-primary);
   margin-bottom: 1rem;
 }
 
 p {
-  color: #7f8c8d;
+  color: var(--color-text-secondary);
   margin-bottom: 1rem;
 }
 
 .error-message {
-  color: #c0392b;
+  color: var(--color-danger);
   font-weight: 500;
 }
 
@@ -192,7 +192,7 @@ p {
 }
 
 .login-link a {
-  color: #3498db;
+  color: var(--color-accent);
   text-decoration: none;
 }
 
@@ -203,13 +203,13 @@ p {
 .resend-section {
   margin-top: 2rem;
   padding-top: 2rem;
-  border-top: 1px solid #e1e8ed;
+  border-top: 1px solid var(--color-border);
 }
 
 .resend-section > p {
   margin-bottom: 1rem;
   font-weight: 500;
-  color: #2c3e50;
+  color: var(--color-text-primary);
 }
 
 .resend-form {
@@ -221,22 +221,25 @@ p {
 .resend-input {
   flex: 1;
   padding: 0.5rem;
-  border: 1px solid #ddd;
-  border-radius: 4px;
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-sm);
   font-size: 1rem;
+  background: var(--color-surface);
+  color: var(--color-text-primary);
 }
 
 .resend-input:focus {
   outline: none;
-  border-color: #3498db;
+  border-color: var(--color-accent);
+  box-shadow: 0 0 0 3px color-mix(in srgb, var(--color-accent) 15%, transparent);
 }
 
 .resend-message {
   padding: 0.75rem;
-  background: #d4edda;
-  border-left: 3px solid #28a745;
-  border-radius: 4px;
-  color: #155724;
+  background: color-mix(in srgb, var(--color-success) 10%, transparent);
+  border-left: 3px solid var(--color-success);
+  border-radius: var(--radius-sm);
+  color: var(--color-success);
   text-align: left;
 }
 </style>