:root {
    --primary-color: #2563eb;
    --secondary-color: #1e40af;
    --accent-color: #3b82f6;
    --text-dark: #1f2937;
    --text-light: #6b7280;
    --bg-light: #f8fafc;
    --border-light: #e5e7eb;
  }
  
  body { 
    padding-top: 4.5rem; 
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
  }
  
  /* Navigation moderne */
  .navbar {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%) !important;
    box-shadow: 0 2px 20px rgba(37, 99, 235, 0.15);
    padding: 0.8rem 0;
    backdrop-filter: blur(10px);
  }
  
  .navbar-brand {
    font-weight: 700;
    font-size: 1.4rem;
    color: white !important;
    transition: all 0.3s ease;
  }
  
  .navbar-brand:hover {
    transform: translateY(-1px);
    text-shadow: 0 2px 10px rgba(255,255,255,0.3);
  }
  
  .navbar-nav .nav-link {
    color: rgba(255, 255, 255, 0.9) !important;
    font-weight: 500;
    margin: 0 0.3rem;
    padding: 0.5rem 0.8rem !important;
    border-radius: 8px;
    transition: all 0.3s ease;
    position: relative;
  }
  
  .navbar-nav .nav-link:hover {
    color: white !important;
    background: rgba(255, 255, 255, 0.1);
    transform: translateY(-1px);
    box-shadow: 0 4px 15px rgba(255,255,255,0.1);
  }
  
  .navbar-nav .nav-link:active {
    background: rgba(255, 255, 255, 0.2);
  }
  
  /* Badge pour messages */
  .navbar-nav .badge {
    font-size: 0.7rem;
    padding: 0.25rem 0.4rem;
    border-radius: 10px;
    animation: pulse 2s infinite;
  }
  
  @keyframes pulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.1); }
    100% { transform: scale(1); }
  }
  
  /* Dropdown menus */
  .dropdown-menu {
    background: rgba(255, 255, 255, 0.98);
    border: none;
    border-radius: 15px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.15);
    padding: 0.5rem 0;
    margin-top: 0.5rem;
    backdrop-filter: blur(10px);
  }
  
  .dropdown-item {
    color: var(--text-dark);
    padding: 0.6rem 1.5rem;
    font-weight: 500;
    transition: all 0.3s ease;
    border-radius: 8px;
    margin: 0.1rem 0.5rem;
  }
  
  .dropdown-item:hover {
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    color: white;
    transform: translateX(5px);
  }
  
  .dropdown-item i {
    width: 20px;
    text-align: center;
  }
  
  .dropdown-toggle::after {
    margin-left: 0.5rem;
    transition: transform 0.3s ease;
  }
  
  .dropdown.show .dropdown-toggle::after {
    transform: rotate(180deg);
  }
  
  /* Utilisateur connecté */
  .navbar-text {
    background: rgba(255, 255, 255, 0.1);
    padding: 0.4rem 0.8rem;
    border-radius: 20px;
    font-size: 0.9rem;
    border: 1px solid rgba(255, 255, 255, 0.2);
  }
  
  /* Responsive navbar */
  .navbar-toggler {
    border: none;
    padding: 0.25rem 0.5rem;
  }
  
  .navbar-toggler:focus {
    box-shadow: none;
  }
  
  .navbar-toggler-icon {
    background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 30 30'%3e%3cpath stroke='rgba%28255, 255, 255, 0.9%29' stroke-linecap='round' stroke-miterlimit='10' stroke-width='2' d='M4 7h22M4 15h22M4 23h22'/%3e%3c/svg%3e");
  }
  
  /* Menu mobile */
  @media (max-width: 991.98px) {
    .navbar-collapse {
      background: #2563ebf2;
      margin-top: 1rem;
      padding: 1rem;
      border-radius: 15px;
      backdrop-filter: blur(10px);
    }
    
    .navbar-nav .nav-link {
      margin: 0.2rem 0;
      padding: 0.8rem 1rem !important;
    }
    
    .navbar-text {
      margin: 0.5rem 0;
      display: inline-block;
    }
  }
  
  /* Container principal */
  .container {
    max-width: 1200px;
    margin: 0 auto;
    margin-top: 50px;
  }
  
  /* Cards et éléments */
  .card {
    border: none;
    border-radius: 15px;
    box-shadow: 0 5px 25px rgba(0,0,0,0.08);
    transition: all 0.3s ease;
  }
  
  .card:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 40px rgba(0,0,0,0.12);
  }
  
  .card-header {
    background: linear-gradient(135deg, var(--bg-light) 0%, #e0f2fe 100%);
    border-bottom: 1px solid var(--border-light);
    border-radius: 15px 15px 0 0 !important;
    padding: 1.5rem;
  }
  
  /* Boutons */
  .btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    border: none;
    border-radius: 10px;
    padding: 0.6rem 1.5rem;
    font-weight: 500;
    transition: all 0.3s ease;
  }
  
  .btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 8px 25px rgba(37, 99, 235, 0.3);
  }
  
  /* Tables */
  .table {
    border-radius: 10px;
    overflow: hidden;
    font-size: 14px;
  }
  
  .table thead th {
    background: var(--bg-light);
    border: none;
    font-weight: 600;
    color: var(--text-dark);
  }