:root {
  --primary: #3b82f6;
  --primary-dark: #2563eb;
  --primary-light: #60a5fa;
  --secondary: #64748b;
  --success: #10b981;
  --danger: #ef4444;
  --warning: #f59e0b;
  --info: #06b6d4;
  
  --bg-primary: #ffffff;
  --bg-secondary: #f8fafc;
  --bg-tertiary: #f1f5f9;
  
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;
  --text-light: #ffffff;
  
  --border: #e2e8f0;
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow: 0 1px 3px 0 rgb(0 0 0 / 0.1), 0 1px 2px -1px rgb(0 0 0 / 0.1);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  
  --radius: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  
  --transition: all 0.2s ease-in-out;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--bg-secondary);
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1rem;
}

.container-sm { max-width: 640px; }
.container-md { max-width: 768px; }
.container-lg { max-width: 1024px; }
.container-xl { max-width: 1280px; }

.card {
  background: var(--bg-primary);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  overflow: hidden;
  transition: var(--transition);
}

.card:hover {
  box-shadow: var(--shadow-md);
}

.card-header {
  padding: 1.5rem;
  border-bottom: 1px solid var(--border);
  background: var(--bg-primary);
}

.card-body {
  padding: 1.5rem;
}

.card-footer {
  padding: 1.5rem;
  border-top: 1px solid var(--border);
  background: var(--bg-secondary);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.625rem 1.25rem;
  font-size: 0.95rem;
  font-weight: 500;
  line-height: 1.5;
  border-radius: var(--radius);
  border: none;
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
  white-space: nowrap;
}

.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.btn-primary {
  background: var(--primary);
  color: var(--text-light);
}

.btn-primary:hover:not(:disabled) {
  background: var(--primary-dark);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-secondary {
  background: var(--secondary);
  color: var(--text-light);
}

.btn-secondary:hover:not(:disabled) {
  background: #475569;
}

.btn-success {
  background: var(--success);
  color: var(--text-light);
}

.btn-success:hover:not(:disabled) {
  background: #059669;
}

.btn-danger {
  background: var(--danger);
  color: var(--text-light);
}

.btn-danger:hover:not(:disabled) {
  background: #dc2626;
}

.btn-sm {
  padding: 0.375rem 0.75rem;
  font-size: 0.875rem;
}

.btn-lg {
  padding: 0.75rem 1.5rem;
  font-size: 1.1rem;
}

.form-group {
  margin-bottom: 1.5rem;
}

.form-label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 500;
  color: var(--text-primary);
  font-size: 0.95rem;
}

.form-control {
  width: 100%;
  padding: 0.625rem 0.875rem;
  font-size: 1rem;
  line-height: 1.5;
  color: var(--text-primary);
  background: var(--bg-primary);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: var(--transition);
}

.form-control:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.form-control::placeholder {
  color: var(--text-muted);
}

.form-select {
  appearance: none;
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3e%3cpath fill='none' stroke='%2364748b' stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M2 5l6 6 6-6'/%3e%3c/svg%3e");
  background-repeat: no-repeat;
  background-position: right 0.75rem center;
  background-size: 1.25rem 1.25rem;
  padding-right: 2.5rem;
}

.form-textarea {
  min-height: 100px;
  resize: vertical;
}

.alert {
  padding: 1rem 1.5rem;
  border-radius: var(--radius);
  margin-bottom: 1.5rem;
  border: 1px solid transparent;
}

.alert-success {
  background: #ecfdf5;
  border-color: #d1fae5;
  color: #065f46;
}

.alert-danger {
  background: #fef2f2;
  border-color: #fee2e2;
  color: #991b1b;
}

.alert-warning {
  background: #fffbeb;
  border-color: #fde68a;
  color: #92400e;
}

.alert-info {
  background: #ecfeff;
  border-color: #cffafe;
  color: #155e75;
}

.table-container {
  overflow-x: auto;
}

.table {
  width: 100%;
  border-collapse: collapse;
  background: var(--bg-primary);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}

.table th,
.table td {
  padding: 0.875rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.table th {
  background: var(--bg-tertiary);
  font-weight: 600;
  color: var(--text-primary);
  text-transform: uppercase;
  font-size: 0.8rem;
  letter-spacing: 0.025em;
}

.table tbody tr:hover {
  background: var(--bg-secondary);
}

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

.badge {
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0.625rem;
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: 9999px;
}

.badge-primary {
  background: #dbeafe;
  color: #1e40af;
}

.badge-success {
  background: #d1fae5;
  color: #065f46;
}

.badge-danger {
  background: #fee2e2;
  color: #991b1b;
}

.badge-warning {
  background: #fef3c7;
  color: #92400e;
}

.navbar {
  background: var(--bg-primary);
  border-bottom: 1px solid var(--border);
  padding: 0.75rem 0;
  box-shadow: var(--shadow-sm);
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.navbar-brand {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.navbar-nav {
  display: flex;
  gap: 1rem;
  list-style: none;
}

.nav-link {
  padding: 0.5rem 1rem;
  color: var(--text-secondary);
  text-decoration: none;
  border-radius: var(--radius);
  transition: var(--transition);
  font-weight: 500;
}

.nav-link:hover,
.nav-link.active {
  color: var(--primary);
  background: #eff6ff;
}

.loading {
  display: inline-block;
  width: 1.25rem;
  height: 1.25rem;
  border: 2px solid var(--border);
  border-radius: 50%;
  border-top-color: var(--primary);
  animation: spin 0.8s linear infinite;
}

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

.toast-container {
  position: fixed;
  top: 1rem;
  right: 1rem;
  z-index: 9999;
  max-width: 350px;
}

.toast {
  background: var(--bg-primary);
  border-radius: var(--radius-lg);
  padding: 1rem 1.25rem;
  margin-bottom: 0.75rem;
  box-shadow: var(--shadow-lg);
  border-left: 4px solid var(--primary);
  animation: slideIn 0.3s ease-out;
}

@keyframes slideIn {
  from {
    transform: translateX(100%);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

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

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@media (max-width: 768px) {
  .container {
    padding: 0 0.75rem;
  }
  
  .card-header,
  .card-body,
  .card-footer {
    padding: 1rem;
  }
  
  .table {
    font-size: 0.875rem;
  }
  
  .table th,
  .table td {
    padding: 0.5rem;
  }
  
  .navbar .container {
    flex-direction: column;
    gap: 0.75rem;
  }
  
  .navbar-nav {
    flex-direction: column;
    width: 100%;
  }
  
  .nav-link {
    text-align: center;
  }
}