:root {
  /* Color Palette */
  --primary: #1e3a5f;
  --secondary: #2d8cf0;
  --accent: #00b894;
  --bg-color: #f0f2f5;
  --sidebar-bg: #1a2332;
  --card-bg: #ffffff;
  --text-main: #333333;
  --text-muted: #6c757d;
  --success: #00b894;
  --warning: #f39c12;
  --danger: #e74c3c;
  --info: #17a2b8;
  --border: #e0e0e0;
  
  /* Dimensions & Spacing */
  --sidebar-width: 260px;
  --sidebar-collapsed-width: 70px;
  --header-height: 60px;
  --transition-speed: 0.3s;
  
  /* Shadows */
  --shadow-sm: 0 2px 4px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.1);
  --shadow-lg: 0 10px 15px rgba(0,0,0,0.1);
}

/* Reset & Base */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  background-color: var(--bg-color);
  color: var(--text-main);
  line-height: 1.5;
  font-size: 14px;
}

a {
  color: var(--secondary);
  text-decoration: none;
}
a:hover { text-decoration: underline; }

h1, h2, h3, h4, h5, h6 { margin-bottom: 0.5rem; font-weight: 600; }

/* Layout */
.app-container {
  display: flex;
  min-height: 100vh;
  width: 100%;
}

/* Sidebar */
.sidebar {
  width: var(--sidebar-width);
  background-color: var(--sidebar-bg);
  color: #fff;
  transition: width var(--transition-speed) ease;
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  position: fixed;
  height: 100vh;
  z-index: 1000;
  overflow-y: auto;
}
.sidebar.collapsed { width: var(--sidebar-collapsed-width); }

.sidebar-header {
  height: var(--header-height);
  display: flex;
  align-items: center;
  padding: 0 20px;
  background-color: rgba(0,0,0,0.2);
  border-bottom: 1px solid rgba(255,255,255,0.1);
  justify-content: space-between;
}
.sidebar-logo {
  font-weight: 700;
  font-size: 18px;
  white-space: nowrap;
  overflow: hidden;
}
.sidebar.collapsed .sidebar-logo { display: none; }

.nav-group {
  margin-top: 15px;
  padding-bottom: 10px;
}
.nav-header {
  font-size: 11px;
  text-transform: uppercase;
  color: rgba(255,255,255,0.4);
  padding: 10px 20px;
  letter-spacing: 1px;
  white-space: nowrap;
}
.sidebar.collapsed .nav-header { text-align: center; font-size: 0; }
.sidebar.collapsed .nav-header::after { content: '...'; font-size: 14px; }

.nav-item {
  display: flex;
  align-items: center;
  padding: 12px 20px;
  color: rgba(255,255,255,0.7);
  transition: all 0.2s;
  cursor: pointer;
  border-left: 3px solid transparent;
  white-space: nowrap;
}
.nav-item:hover, .nav-item.active {
  background-color: rgba(255,255,255,0.1);
  color: #fff;
  text-decoration: none;
}
.nav-item.active {
  border-left-color: var(--accent);
}
.nav-icon {
  margin-right: 15px;
  font-size: 18px;
  width: 24px;
  text-align: center;
}
.sidebar.collapsed .nav-item { padding: 12px 0; justify-content: center; }
.sidebar.collapsed .nav-icon { margin-right: 0; }
.sidebar.collapsed .nav-text { display: none; }

/* Main Content */
.main-content {
  flex-grow: 1;
  margin-left: var(--sidebar-width);
  transition: margin-left var(--transition-speed) ease;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}
.sidebar.collapsed ~ .main-content { margin-left: var(--sidebar-collapsed-width); }

/* Topbar */
.topbar {
  height: var(--header-height);
  background-color: var(--card-bg);
  box-shadow: var(--shadow-sm);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 20px;
  position: sticky;
  top: 0;
  z-index: 900;
}
.topbar-left, .topbar-right { display: flex; align-items: center; gap: 15px; }

.toggle-sidebar {
  background: none;
  border: none;
  font-size: 20px;
  cursor: pointer;
  color: var(--text-main);
  padding: 5px;
}

.search-bar {
  position: relative;
  display: flex;
  align-items: center;
}
.search-bar input {
  padding: 8px 15px 8px 35px;
  border: 1px solid var(--border);
  border-radius: 20px;
  outline: none;
  width: 250px;
  transition: box-shadow 0.2s;
}
.search-bar input:focus { box-shadow: 0 0 0 3px rgba(45, 140, 240, 0.2); border-color: var(--secondary); }
.search-bar .search-icon {
  position: absolute;
  left: 12px;
  color: var(--text-muted);
}

.user-profile {
  display: flex;
  align-items: center;
  gap: 10px;
  cursor: pointer;
}
.avatar { width: 35px; height: 35px; border-radius: 50%; background-color: var(--primary); color: #fff; display: flex; align-items: center; justify-content: center; font-weight: bold; }

/* Content Area */
.content-wrapper { padding: 20px; flex-grow: 1; }

.page-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
}
.page-title { font-size: 24px; color: var(--primary); }

/* Dashboard Cards */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-bottom: 30px;
}
.stat-card {
  background: var(--card-bg);
  border-radius: 12px;
  padding: 20px;
  box-shadow: var(--shadow-sm);
  display: flex;
  align-items: center;
  transition: transform 0.2s, box-shadow 0.2s;
  border-left: 4px solid var(--primary);
}
.stat-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-md); }
.stat-card.blue { border-left-color: var(--secondary); }
.stat-card.green { border-left-color: var(--success); }
.stat-card.yellow { border-left-color: var(--warning); }
.stat-card.red { border-left-color: var(--danger); }

.stat-icon {
  width: 50px;
  height: 50px;
  border-radius: 10px;
  background-color: rgba(45, 140, 240, 0.1);
  color: var(--secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  margin-right: 15px;
}
.stat-info h3 { margin: 0; font-size: 24px; color: var(--text-main); }
.stat-info p { margin: 0; color: var(--text-muted); font-size: 13px; text-transform: uppercase; letter-spacing: 0.5px; }
.stat-trend { font-size: 12px; margin-top: 5px; display: inline-block; }
.trend-up { color: var(--success); }
.trend-down { color: var(--danger); }

/* Tables */
.card {
  background: var(--card-bg);
  border-radius: 12px;
  box-shadow: var(--shadow-sm);
  margin-bottom: 20px;
  overflow: hidden;
}
.card-header {
  padding: 15px 20px;
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.card-header h3 { margin: 0; font-size: 16px; }
.card-body { padding: 20px; overflow-x: auto; }

.table-responsive { width: 100%; overflow-x: auto; }
.table { width: 100%; border-collapse: collapse; }
.table th, .table td { padding: 12px 15px; text-align: left; border-bottom: 1px solid var(--border); }
.table th { background-color: rgba(0,0,0,0.02); font-weight: 600; color: var(--text-muted); position: sticky; top: 0; z-index: 10; }
.table tbody tr:hover { background-color: rgba(0,0,0,0.01); }
.table tbody tr:last-child td { border-bottom: none; }

.badge {
  padding: 4px 8px;
  border-radius: 12px;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
}
.badge-success { background-color: rgba(0,184,148,0.1); color: var(--success); }
.badge-warning { background-color: rgba(243,156,18,0.1); color: var(--warning); }
.badge-danger { background-color: rgba(231,76,60,0.1); color: var(--danger); }
.badge-secondary { background-color: rgba(108,117,125,0.1); color: var(--text-muted); }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 5px;
  padding: 8px 16px;
  border: none;
  border-radius: 6px;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
  text-decoration: none;
}
.btn:focus { outline: none; box-shadow: 0 0 0 3px rgba(45, 140, 240, 0.3); }
.btn:disabled { opacity: 0.6; cursor: not-allowed; }
.btn-sm { padding: 4px 10px; font-size: 12px; }
.btn-lg { padding: 12px 24px; font-size: 16px; }

.btn-primary { background-color: var(--secondary); color: #fff; }
.btn-primary:hover { background-color: #1a73e8; color: #fff; text-decoration: none; }
.btn-success { background-color: var(--success); color: #fff; }
.btn-success:hover { background-color: #00997a; color: #fff; text-decoration: none; }
.btn-danger { background-color: var(--danger); color: #fff; }
.btn-danger:hover { background-color: #c0392b; color: #fff; text-decoration: none; }
.btn-warning { background-color: var(--warning); color: #fff; }
.btn-warning:hover { background-color: #d68910; color: #fff; text-decoration: none; }
.btn-secondary { background-color: var(--bg-color); color: var(--text-main); border: 1px solid var(--border); }
.btn-secondary:hover { background-color: #e2e6ea; text-decoration: none; }

.btn-icon { padding: 6px; border-radius: 4px; }
.btn-icon-text { display: flex; align-items: center; gap: 5px; }

/* Forms */
.form-group { margin-bottom: 20px; }
.form-label { display: block; margin-bottom: 8px; font-weight: 500; color: var(--text-main); }
.form-control {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 14px;
  transition: border-color 0.2s, box-shadow 0.2s;
  background-color: #fff;
}
.form-control:focus {
  outline: none;
  border-color: var(--secondary);
  box-shadow: 0 0 0 3px rgba(45, 140, 240, 0.1);
}
textarea.form-control { resize: vertical; min-height: 100px; }
.form-help { font-size: 12px; color: var(--text-muted); margin-top: 5px; display: block; }
.form-row { display: flex; gap: 20px; flex-wrap: wrap; }
.form-col { flex: 1; min-width: 250px; }

/* File Upload */
.file-upload-zone {
  border: 2px dashed var(--border);
  border-radius: 8px;
  padding: 30px;
  text-align: center;
  background-color: rgba(0,0,0,0.02);
  transition: all 0.2s;
  cursor: pointer;
  position: relative;
}
.file-upload-zone:hover, .file-upload-zone.dragover {
  border-color: var(--secondary);
  background-color: rgba(45, 140, 240, 0.05);
}
.file-upload-zone input[type="file"] {
  position: absolute;
  top: 0; left: 0; width: 100%; height: 100%;
  opacity: 0; cursor: pointer;
}
.file-upload-icon { font-size: 32px; color: var(--text-muted); margin-bottom: 10px; }

/* Toggle Switch */
.switch { position: relative; display: inline-block; width: 44px; height: 24px; }
.switch input { opacity: 0; width: 0; height: 0; }
.slider {
  position: absolute; cursor: pointer; top: 0; left: 0; right: 0; bottom: 0;
  background-color: #ccc; transition: .4s; border-radius: 24px;
}
.slider:before {
  position: absolute; content: ""; height: 18px; width: 18px; left: 3px; bottom: 3px;
  background-color: white; transition: .4s; border-radius: 50%;
}
input:checked + .slider { background-color: var(--success); }
input:focus + .slider { box-shadow: 0 0 1px var(--success); }
input:checked + .slider:before { transform: translateX(20px); }

/* Breadcrumbs */
.breadcrumb { display: flex; list-style: none; margin-bottom: 20px; font-size: 14px; }
.breadcrumb-item { display: flex; align-items: center; }
.breadcrumb-item a { color: var(--text-muted); }
.breadcrumb-item a:hover { color: var(--secondary); }
.breadcrumb-item + .breadcrumb-item::before { content: "›"; margin: 0 10px; color: var(--text-muted); font-size: 18px; }
.breadcrumb-item.active { color: var(--text-main); font-weight: 500; }

/* Section Cards (Drag & Drop) */
.section-card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 15px;
  margin-bottom: 15px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: all 0.2s;
}
.section-card.disabled { opacity: 0.6; background-color: var(--bg-color); }
.section-drag-handle { cursor: grab; color: var(--text-muted); margin-right: 15px; font-size: 18px; }
.section-drag-handle:active { cursor: grabbing; }
.section-info { flex-grow: 1; display: flex; align-items: center; gap: 15px; }
.section-actions { display: flex; gap: 10px; align-items: center; }

/* Media Gallery Grid */
.media-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 15px; }
.media-item {
  position: relative; border-radius: 8px; overflow: hidden; border: 1px solid var(--border);
  background: var(--bg-color); aspect-ratio: 1; cursor: pointer; transition: all 0.2s;
}
.media-item img { width: 100%; height: 100%; object-fit: cover; }
.media-overlay {
  position: absolute; top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0,0,0,0.5); display: flex; align-items: center; justify-content: center;
  opacity: 0; transition: opacity 0.2s; gap: 10px;
}
.media-item:hover .media-overlay { opacity: 1; }
.media-item.selected { border: 3px solid var(--secondary); }
.media-item.selected::after {
  content: '✓'; position: absolute; top: 10px; right: 10px;
  background: var(--secondary); color: white; width: 24px; height: 24px;
  border-radius: 50%; display: flex; align-items: center; justify-content: center;
}

/* Modals */
.modal-backdrop {
  position: fixed; top: 0; left: 0; width: 100vw; height: 100vh;
  background: rgba(0,0,0,0.5); z-index: 1050; display: none;
  align-items: center; justify-content: center; opacity: 0; transition: opacity 0.3s;
}
.modal-backdrop.show { display: flex; opacity: 1; }
.modal-content {
  background: var(--card-bg); border-radius: 12px; width: 100%; max-width: 500px;
  box-shadow: var(--shadow-lg); transform: translateY(-20px); transition: transform 0.3s;
  margin: 20px;
}
.modal-backdrop.show .modal-content { transform: translateY(0); }
.modal-header { padding: 15px 20px; border-bottom: 1px solid var(--border); display: flex; justify-content: space-between; align-items: center; }
.modal-title { font-size: 18px; margin: 0; }
.modal-close { background: none; border: none; font-size: 24px; cursor: pointer; color: var(--text-muted); }
.modal-body { padding: 20px; }
.modal-footer { padding: 15px 20px; border-top: 1px solid var(--border); display: flex; justify-content: flex-end; gap: 10px; }

/* Toasts / Notifications */
.toast-container { position: fixed; top: 20px; right: 20px; z-index: 1100; display: flex; flex-direction: column; gap: 10px; }
.toast {
  min-width: 250px; background: var(--card-bg); border-left: 4px solid var(--info);
  border-radius: 6px; box-shadow: var(--shadow-md); display: flex;
  align-items: center; justify-content: space-between; padding: 12px 15px;
  animation: slideInRight 0.3s ease forwards;
}
.toast.success { border-left-color: var(--success); }
.toast.error { border-left-color: var(--danger); }
.toast.warning { border-left-color: var(--warning); }
.toast.fade-out { animation: fadeOutRight 0.3s ease forwards; }
@keyframes slideInRight { from { transform: translateX(100%); opacity: 0; } to { transform: translateX(0); opacity: 1; } }
@keyframes fadeOutRight { from { transform: translateX(0); opacity: 1; } to { transform: translateX(100%); opacity: 0; } }

/* Tabs */
.tabs { border-bottom: 1px solid var(--border); display: flex; gap: 20px; margin-bottom: 20px; overflow-x: auto; }
.tab-item {
  padding: 10px 5px; cursor: pointer; border-bottom: 2px solid transparent;
  color: var(--text-muted); font-weight: 500; white-space: nowrap; transition: all 0.2s;
}
.tab-item:hover { color: var(--text-main); }
.tab-item.active { color: var(--secondary); border-bottom-color: var(--secondary); }
.tab-pane { display: none; }
.tab-pane.active { display: block; animation: fadeIn 0.3s ease; }
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }

/* Rich Text Editor */
.rte-container { border: 1px solid var(--border); border-radius: 6px; overflow: hidden; }
.rte-toolbar {
  background: var(--bg-color); padding: 8px; border-bottom: 1px solid var(--border);
  display: flex; gap: 5px; flex-wrap: wrap;
}
.rte-toolbar button {
  background: #fff; border: 1px solid var(--border); border-radius: 4px; padding: 5px 8px;
  cursor: pointer; transition: background 0.2s;
}
.rte-toolbar button:hover { background: #e2e6ea; }
.rte-content { min-height: 200px; padding: 15px; outline: none; background: #fff; }

/* Activity Timeline */
.timeline { position: relative; padding-left: 30px; }
.timeline::before { content: ''; position: absolute; left: 14px; top: 0; bottom: 0; width: 2px; background: var(--border); }
.timeline-item { position: relative; margin-bottom: 20px; }
.timeline-icon {
  position: absolute; left: -30px; top: 0; width: 30px; height: 30px; border-radius: 50%;
  background: var(--bg-color); border: 2px solid var(--secondary); display: flex; align-items: center; justify-content: center; z-index: 1;
}
.timeline-content { background: var(--card-bg); padding: 15px; border-radius: 8px; border: 1px solid var(--border); margin-left: 15px; }
.timeline-time { font-size: 12px; color: var(--text-muted); margin-bottom: 5px; }

/* Quick Actions */
.quick-actions { display: grid; grid-template-columns: repeat(auto-fill, minmax(120px, 1fr)); gap: 15px; }
.quick-action-btn {
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  gap: 10px; padding: 20px 10px; background: var(--card-bg); border: 1px solid var(--border);
  border-radius: 12px; color: var(--text-main); transition: all 0.2s;
}
.quick-action-btn:hover { border-color: var(--secondary); color: var(--secondary); transform: translateY(-2px); box-shadow: var(--shadow-sm); text-decoration: none;}
.quick-action-icon { font-size: 24px; color: var(--secondary); }

/* Responsive Design */
@media (max-width: 1024px) {
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .form-row { flex-direction: column; gap: 0; }
}
@media (max-width: 768px) {
  .sidebar { transform: translateX(-100%); width: var(--sidebar-width); }
  .sidebar.mobile-open { transform: translateX(0); }
  .main-content { margin-left: 0 !important; }
  .stats-grid { grid-template-columns: 1fr; }
  .card-header { flex-direction: column; align-items: flex-start; gap: 10px; }
  .sidebar-backdrop {
    position: fixed; top: 0; left: 0; right: 0; bottom: 0; background: rgba(0,0,0,0.5); z-index: 999; display: none;
  }
  .sidebar-backdrop.show { display: block; }
}

/* Print Styles */
@media print {
  .sidebar, .topbar, .btn, .no-print { display: none !important; }
  .main-content { margin-left: 0 !important; padding: 0; }
  .card { box-shadow: none; border: 1px solid #ccc; page-break-inside: avoid; }
}