:root {
    --primary: #4f46e5;
    --primary-light: #6366f1;
    --primary-dark: #3730a3;
    --secondary: #7c3aed;
    --accent: #06b6d4;
    --accent-light: #22d3ee;
    --danger: #dc2626;
    --danger-light: #ef4444;
    --success: #059669;
    --success-light: #10b981;
    --warning: #d97706;
    --warning-light: #f59e0b;
    --info: #0891b2;
    --info-light: #06b6d4;
    --dark: #0f172a;
    --dark-light: #1e293b;
    --light: #f8fafc;
    --light-gray: #f1f5f9;
    --gray: #64748b;
    --gray-light: #e2e8f0;
    --gray-lighter: #f8fafc;
    --sidebar-width: 280px;
    --header-height: 70px;
    --border-radius: 16px;
    --border-radius-sm: 8px;
    --border-radius-lg: 20px;
    --box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --box-shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --box-shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-fast: all 0.15s cubic-bezier(0.4, 0, 0.2, 1);
    --gradient-primary: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
    --gradient-secondary: linear-gradient(135deg, var(--secondary) 0%, #8b5cf6 100%);
    --gradient-accent: linear-gradient(135deg, var(--accent) 0%, var(--accent-light) 100%);
  }
  
  /* Modern Reset */
  * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }
  
  body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
    color: var(--dark);
    line-height: 1.6;
    font-size: 14px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
  }
  
  /* Typography */
  h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.25;
    letter-spacing: -0.025em;
    color: var(--dark);
  }

  h1 { font-size: 2.25rem; }
  h2 { font-size: 1.875rem; }
  h3 { font-size: 1.5rem; }
  h4 { font-size: 1.25rem; }
  h5 { font-size: 1.125rem; }
  h6 { font-size: 1rem; }

  p {
    margin-bottom: 1rem;
    line-height: 1.7;
  }

  .text-gradient {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
  }
  
  /* Layout */
  .app-container {
    display: grid;
    grid-template-columns: var(--sidebar-width) 1fr;
    grid-template-rows: var(--header-height) 1fr;
    min-height: 100vh;
  }
  
  .sidebar {
    grid-column: 1;
    grid-row: 1 / -1;
    background: linear-gradient(180deg, white 0%, var(--light-gray) 100%);
    border-right: 1px solid var(--gray-light);
    padding: 2rem 1.5rem;
    position: fixed;
    width: var(--sidebar-width);
    height: 100vh;
    z-index: 100;
    box-shadow: var(--box-shadow);
  }
  
  .main-content {
    grid-column: 2;
    grid-row: 2;
    padding: 2rem;
  }
  
  .header {
    grid-column: 2;
    grid-row: 1;
    background: white;
    border-bottom: 1px solid var(--gray-light);
    padding: 0 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: fixed;
    width: initial;
    height: var(--header-height);
    z-index: 90;
  }
  
  /* Sidebar Styles */
  .sidebar-header {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 2rem;
    padding-bottom: 1.5rem;
    border-bottom: 1px solid var(--gray-light);
  }
  
  .sidebar-header h2 {
    font-size: 1.25rem;
    color: var(--primary);
  }
  
  .sidebar-nav {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
  }
  
  .nav-link {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.875rem 1rem;
    border-radius: var(--border-radius);
    color: var(--gray);
    text-decoration: none;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
  }

  .nav-link::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: var(--gradient-primary);
    transition: var(--transition);
    z-index: -1;
  }

  .nav-link:hover {
    color: white;
    transform: translateX(4px);
  }

  .nav-link:hover::before {
    left: 0;
  }

  .nav-link.active {
    background: var(--gradient-primary);
    color: white;
    font-weight: 600;
    box-shadow: 0 4px 14px 0 rgba(79, 70, 229, 0.25);
  }
  
  .nav-link i {
    font-size: 1.25rem;
  }
  
  /* Header Styles */
  .search-bar {
    position: relative;
    width: 300px;
  }
  
  .search-bar input {
    width: 100%;
    padding: 0.5rem 1rem 0.5rem 2.5rem;
    border-radius: var(--border-radius);
    border: 1px solid var(--gray-light);
    background: var(--light);
    font-size: 0.875rem;
    transition: var(--transition);
  }
  
  .search-bar input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(67, 97, 238, 0.15);
  }
  
  .search-bar i {
    position: absolute;
    left: 1rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--gray);
  }
  
  .user-menu {
    display: flex;
    align-items: center;
    gap: 1rem;
  }
  
  .user-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: var(--primary);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    cursor: pointer;
  }
  
  /* Card Styles */
  .card {
    background: white;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    padding: 2rem;
    margin-bottom: 2rem;
    transition: var(--transition);
    border: 1px solid rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(10px);
    position: relative;
    overflow: hidden;
  }

  .card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--gradient-primary);
    opacity: 0;
    transition: var(--transition);
  }

  .card:hover {
    box-shadow: var(--box-shadow-xl);
    transform: translateY(-2px);
    border-color: rgba(79, 70, 229, 0.1);
  }

  .card:hover::before {
    opacity: 1;
  }

  .card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--gray-light);
  }

  .card-title {
    font-size: 1.5rem;
    color: var(--dark);
    font-weight: 700;
    margin: 0;
  }
  
  /* Button Styles */
  .btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border-radius: var(--border-radius);
    font-weight: 600;
    font-size: 0.875rem;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    position: relative;
    overflow: hidden;
    text-decoration: none;
  }

  .btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: var(--transition);
  }

  .btn:hover::before {
    left: 100%;
  }

  .btn-primary {
    background: var(--gradient-primary);
    color: white;
    box-shadow: 0 4px 14px 0 rgba(79, 70, 229, 0.39);
  }

  .btn-primary:hover {
    background: var(--gradient-primary);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px 0 rgba(79, 70, 229, 0.5);
  }

  .btn-outline {
    background: transparent;
    border: 2px solid var(--gray-light);
    color: var(--dark);
  }

  .btn-outline:hover {
    background: var(--gradient-primary);
    border-color: var(--primary);
    color: white;
    transform: translateY(-1px);
  }

  .btn-outline-secondary {
    background: transparent;
    border: 2px solid var(--gray);
    color: var(--gray);
  }

  .btn-outline-secondary:hover {
    background: var(--gray);
    color: white;
    transform: translateY(-1px);
  }

  .btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.75rem;
    border-radius: var(--border-radius-sm);
  }

  .btn-icon {
    width: 2.5rem;
    height: 2.5rem;
    padding: 0;
    border-radius: 50%;
  }

  .btn-success {
    background: var(--gradient-accent);
    color: white;
  }

  .btn-danger {
    background: linear-gradient(135deg, var(--danger) 0%, var(--danger-light) 100%);
    color: white;
  }
  
  /* Table Styles */
  .table-responsive {
    overflow-x: auto;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    background: white;
  }

  .table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.875rem;
    margin: 0;
  }

  .table th {
    text-align: left;
    padding: 1rem 1.5rem;
    background: linear-gradient(135deg, var(--light-gray) 0%, var(--gray-light) 100%);
    font-weight: 700;
    color: var(--dark);
    border-bottom: 2px solid var(--gray-light);
    position: sticky;
    top: 0;
    z-index: 10;
  }

  .table td {
    padding: 1rem 1.5rem;
    border-bottom: 1px solid var(--gray-lighter);
    transition: var(--transition);
  }

  .table tr:last-child td {
    border-bottom: none;
  }

  .table tr:hover td {
    background: linear-gradient(135deg, rgba(79, 70, 229, 0.02) 0%, rgba(79, 70, 229, 0.05) 100%);
    transform: scale(1.01);
  }

  .table tr {
    transition: var(--transition);
  }
  
  /* Badge Styles */
  .badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.375rem 0.875rem;
    border-radius: 2rem;
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    border: 1px solid transparent;
  }

  .badge-primary {
    background: var(--gradient-primary);
    color: white;
  }

  .badge-success {
    background: linear-gradient(135deg, var(--success) 0%, var(--success-light) 100%);
    color: white;
  }

  .badge-danger {
    background: linear-gradient(135deg, var(--danger) 0%, var(--danger-light) 100%);
    color: white;
  }

  .badge-warning {
    background: linear-gradient(135deg, var(--warning) 0%, var(--warning-light) 100%);
    color: white;
  }

  .badge-info {
    background: linear-gradient(135deg, var(--info) 0%, var(--info-light) 100%);
    color: white;
  }
  
  /* Form Styles */
  .form-group {
    margin-bottom: 1.5rem;
  }

  .form-label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    font-size: 0.875rem;
    color: var(--dark);
    letter-spacing: -0.01em;
  }

  .form-control {
    width: 100%;
    padding: 0.875rem 1rem;
    border: 2px solid var(--gray-light);
    border-radius: var(--border-radius);
    font-size: 0.875rem;
    transition: var(--transition);
    background: white;
    color: var(--dark);
  }

  .form-control:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
    transform: translateY(-1px);
  }

  .form-control-sm {
    padding: 0.5rem 0.75rem;
    font-size: 0.75rem;
    border-radius: var(--border-radius-sm);
  }

  .form-control:hover {
    border-color: var(--primary-light);
  }
  
  /* Grid System */
  .grid {
    display: grid;
    gap: 1.5rem;
  }
  
  .grid-cols-3 {
    grid-template-columns: repeat(3, 1fr);
  }
  
  /* Utility Classes */
  .mb-4 { margin-bottom: 1rem; }
  .mb-6 { margin-bottom: 1.5rem; }
  .mb-8 { margin-bottom: 2rem; }

  .p-4 { padding: 1rem; }
  .p-6 { padding: 1.5rem; }
  .p-8 { padding: 2rem; }

  .text-primary { color: var(--primary); }
  .text-success { color: var(--success); }
  .text-danger { color: var(--danger); }
  .text-warning { color: var(--warning); }
  .text-info { color: var(--info); }
  .text-muted { color: var(--gray); }

  .bg-primary { background: var(--gradient-primary); }
  .bg-secondary { background: var(--gradient-secondary); }
  .bg-accent { background: var(--gradient-accent); }

  .shadow-sm { box-shadow: var(--box-shadow); }
  .shadow-lg { box-shadow: var(--box-shadow-lg); }
  .shadow-xl { box-shadow: var(--box-shadow-xl); }

  .rounded { border-radius: var(--border-radius); }
  .rounded-sm { border-radius: var(--border-radius-sm); }
  .rounded-lg { border-radius: var(--border-radius-lg); }

  .d-flex { display: flex; }
  .d-block { display: block; }
  .d-none { display: none; }

  .justify-center { justify-content: center; }
  .justify-between { justify-content: space-between; }
  .align-center { align-items: center; }

  .w-100 { width: 100%; }
  .h-100 { height: 100%; }

  .text-center { text-align: center; }
  .text-left { text-align: left; }
  .text-right { text-align: right; }
  
  /* Animations */
  @keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
  }

  @keyframes slideIn {
    from { opacity: 0; transform: translateX(-20px); }
    to { opacity: 1; transform: translateX(0); }
  }

  @keyframes bounceIn {
    0% { opacity: 0; transform: scale(0.3); }
    50% { opacity: 1; transform: scale(1.05); }
    70% { transform: scale(0.9); }
    100% { opacity: 1; transform: scale(1); }
  }

  @keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
  }

  .animate-fade {
    animation: fadeIn 0.3s ease-out forwards;
  }

  .animate-slide {
    animation: slideIn 0.3s ease-out forwards;
  }

  .animate-bounce {
    animation: bounceIn 0.6s ease-out forwards;
  }

  .animate-pulse {
    animation: pulse 2s infinite;
  }

  /* Custom Scrollbar */
  ::-webkit-scrollbar {
    width: 8px;
    height: 8px;
  }

  ::-webkit-scrollbar-track {
    background: var(--light-gray);
    border-radius: 4px;
  }

  ::-webkit-scrollbar-thumb {
    background: var(--gradient-primary);
    border-radius: 4px;
    transition: var(--transition);
  }

  ::-webkit-scrollbar-thumb:hover {
    background: var(--primary-dark);
  }

  /* Loading Animation */
  .loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid var(--gray-light);
    border-radius: 50%;
    border-top-color: var(--primary);
    animation: spin 1s ease-in-out infinite;
  }

  @keyframes spin {
    to { transform: rotate(360deg); }
  }

  /* Glass Effect */
  .glass {
    background: rgba(255, 255, 255, 0.25);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.18);
  }

  /* Gradient Text */
  .gradient-text {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
  }

  /* Hover Effects */
  .hover-lift {
    transition: var(--transition);
  }

  .hover-lift:hover {
    transform: translateY(-4px);
    box-shadow: var(--box-shadow-xl);
  }

  /* Focus Styles */
  .focus-ring:focus {
    outline: none;
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.3);
  }
  
  /* Clients List Header Styles */
.clients-list-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.5rem;
  background: var(--gradient-primary);
  color: white;
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow);
  margin-bottom: 1.5rem;
}

.clients-list-header h1 {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 0;
}

.clients-list-header .actions {
  display: flex;
  gap: 0.5rem;
}

.clients-list-header .btn {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
  border-radius: var(--border-radius-sm);
}

.clients-list-header .btn-add {
  background: var(--success);
  color: white;
}

.clients-list-header .btn-export {
  background: var(--info);
  color: white;
}
  
  /* Responsive */
  @media (max-width: 1024px) {
    .grid-cols-3 {
      grid-template-columns: repeat(2, 1fr);
    }

    .card {
      padding: 1.5rem;
    }

    .sidebar {
      width: 240px;
    }
  }

  @media (max-width: 768px) {
    :root {
      --sidebar-width: 100%;
      --header-height: 60px;
    }

    .app-container {
      grid-template-columns: 1fr;
      grid-template-rows: var(--header-height) 1fr;
    }

    .sidebar {
      grid-column: 1;
      grid-row: 1;
      width: 100%;
      height: auto;
      position: static;
      border-right: none;
      border-bottom: 1px solid var(--gray-light);
      padding: 1rem;
      box-shadow: none;
    }

    .header {
      grid-column: 1;
      width: 100%;
      padding: 0 1rem;
    }

    .main-content {
      grid-column: 1;
      grid-row: 2;
      padding: 1rem;
      margin-top: 0;
    }

    .card {
      padding: 1rem;
      margin-bottom: 1rem;
    }

    .card-header {
      flex-direction: column;
      align-items: flex-start;
      gap: 1rem;
    }

    .modal-container {
      margin: 1rem;
      max-width: none;
    }

    .modal-header,
    .modal-body,
    .modal-footer {
      padding: 1rem;
    }

    .btn {
      width: 100%;
      margin-bottom: 0.5rem;
    }

    .modal-footer {
      flex-direction: column;
      gap: 0.5rem;
    }

    .table-responsive {
      font-size: 0.75rem;
    }

    .table th,
    .table td {
      padding: 0.5rem;
    }
  }

  @media (max-width: 480px) {
    .sidebar-nav {
      flex-direction: row;
      overflow-x: auto;
      gap: 0.5rem;
      padding-bottom: 0.5rem;
    }

    .nav-link {
      flex-shrink: 0;
      padding: 0.5rem;
      font-size: 0.75rem;
    }

    .nav-link span {
      display: none;
    }

    .card-title {
      font-size: 1.25rem;
    }

    .search-bar {
      width: 200px;
    }
  }

  /* Modal Styles */
  .modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(15, 23, 42, 0.6);
    backdrop-filter: blur(8px);
    display: flex;
    align-items: flex-start;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    padding-top: 5%;
    overflow-y: auto;
  }

  .modal-overlay.active {
    opacity: 1;
    visibility: visible;
  }

  .modal-container {
    background: white;
    border-radius: var(--border-radius-lg);
    box-shadow: var(--box-shadow-xl);
    width: 100%;
    max-width: 500px;
    max-height: 90vh;
    overflow-y: auto;
    transform: translateY(20px) scale(0.95);
    transition: var(--transition);
    border: 1px solid rgba(255, 255, 255, 0.2);
  }

  .modal-overlay.active .modal-container {
    transform: translateY(0) scale(1);
  }

  .modal-header {
    padding: 2rem;
    border-bottom: 1px solid var(--gray-light);
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: linear-gradient(135deg, var(--light-gray) 0%, white 100%);
  }

  .modal-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin: 0;
    color: var(--dark);
  }

  .modal-close {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--gray);
    transition: var(--transition);
    width: 2rem;
    height: 2rem;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
  }

  .modal-close:hover {
    color: var(--danger);
    background: rgba(220, 38, 38, 0.1);
  }

  .modal-body {
    padding: 2rem;
  }

  .modal-footer {
    padding: 1.5rem 2rem;
    border-top: 1px solid var(--gray-light);
    display: flex;
    justify-content: flex-end;
    gap: 1rem;
    background: var(--light-gray);
  }