/* Modern CSS with Tailwind-inspired utility classes */
:root {
  --primary: #3b82f6;
  --primary-dark: #2563eb;
  --secondary: #8b5cf6;
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  --gray-50: #f9fafb;
  --gray-100: #f3f4f6;
  --gray-200: #e5e7eb;
  --gray-300: #d1d5db;
  --gray-400: #9ca3af;
  --gray-500: #6b7280;
  --gray-600: #4b5563;
  --gray-700: #374151;
  --gray-800: #1f2937;
  --gray-900: #111827;
}

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

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: var(--gray-50);
  color: var(--gray-900);
  line-height: 1.6;
}

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

/* Navigation */
nav {
  background: white;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
  position: sticky;
  top: 0;
  z-index: 50;
}

.nav-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 0;
}

.nav-brand {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
}

.nav-menu {
  display: flex;
  gap: 1.5rem;
  align-items: center;
  list-style: none;
}

.nav-link {
  text-decoration: none;
  color: var(--gray-700);
  font-weight: 500;
  padding: 0.5rem 1rem;
  border-radius: 0.375rem;
  transition: all 0.2s;
}

.nav-link:hover {
  color: var(--primary);
  background: var(--gray-100);
}

.nav-link.active {
  color: var(--primary);
  background: var(--gray-100);
}

/* Login Page */
.login-container {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
}

.login-card {
  background: white;
  border-radius: 0.5rem;
  padding: 2.5rem;
  width: 100%;
  max-width: 420px;
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
}

.login-header {
  text-align: center;
  margin-bottom: 2rem;
}

.login-title {
  font-size: 1.875rem;
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: 0.5rem;
}

.login-subtitle {
  color: var(--gray-600);
}

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

.form-label {
  display: block;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--gray-700);
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 1px solid var(--gray-300);
  border-radius: 0.375rem;
  font-size: 1rem;
  transition: all 0.2s;
}

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

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

/* Buttons */
.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  font-weight: 600;
  text-align: center;
  text-decoration: none;
  border-radius: 0.375rem;
  border: none;
  cursor: pointer;
  transition: all 0.2s;
  font-size: 1rem;
}

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

.btn-primary:hover {
  background: var(--primary-dark);
}

.btn-secondary {
  background: var(--gray-600);
  color: white;
}

.btn-secondary:hover {
  background: var(--gray-700);
}

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

.btn-success:hover {
  background: #059669;
}

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

.btn-danger:hover {
  background: #dc2626;
}

.btn-sm {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
}

.btn-full {
  width: 100%;
}

/* Cards */
.card {
  background: white;
  border-radius: 0.5rem;
  padding: 1.5rem;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
  margin-bottom: 1.5rem;
}

.card-header {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 1rem;
  color: var(--gray-900);
}

/* Stats Cards */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.stat-card {
  background: white;
  border-radius: 0.5rem;
  padding: 1.5rem;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
  border-left: 4px solid var(--primary);
}

.stat-label {
  font-size: 0.875rem;
  color: var(--gray-600);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.5rem;
}

.stat-value {
  font-size: 2rem;
  font-weight: 700;
  color: var(--gray-900);
}

/* Tables */
.table-container {
  overflow-x: auto;
  background: white;
  border-radius: 0.5rem;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

table {
  width: 100%;
  border-collapse: collapse;
}

thead {
  background: var(--gray-50);
}

th {
  padding: 1rem;
  text-align: left;
  font-weight: 600;
  color: var(--gray-700);
  border-bottom: 2px solid var(--gray-200);
}

td {
  padding: 1rem;
  border-bottom: 1px solid var(--gray-200);
}

tr:hover {
  background: var(--gray-50);
}

/* Badges */
.badge {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  border-radius: 9999px;
  font-size: 0.875rem;
  font-weight: 600;
}

.badge-primary {
  background: rgba(59, 130, 246, 0.1);
  color: var(--primary);
}

.badge-success {
  background: rgba(16, 185, 129, 0.1);
  color: var(--success);
}

.badge-warning {
  background: rgba(245, 158, 11, 0.1);
  color: var(--warning);
}

.badge-danger {
  background: rgba(239, 68, 68, 0.1);
  color: var(--danger);
}

.badge-gray {
  background: rgba(107, 114, 128, 0.1);
  color: var(--gray-600);
}

/* Alerts */
.alert {
  padding: 1rem;
  border-radius: 0.375rem;
  margin-bottom: 1.5rem;
  font-weight: 500;
}

.alert-success {
  background: rgba(16, 185, 129, 0.1);
  color: #065f46;
  border: 1px solid rgba(16, 185, 129, 0.3);
}

.alert-error {
  background: rgba(239, 68, 68, 0.1);
  color: #991b1b;
  border: 1px solid rgba(239, 68, 68, 0.3);
}

.alert-warning {
  background: rgba(245, 158, 11, 0.1);
  color: #92400e;
  border: 1px solid rgba(245, 158, 11, 0.3);
}

.alert-info {
  background: rgba(59, 130, 246, 0.1);
  color: #1e40af;
  border: 1px solid rgba(59, 130, 246, 0.3);
}

/* Utilities */
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }

.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }

.flex { display: flex; }
.justify-between { justify-content: space-between; }
.items-center { align-items: center; }
.gap-2 { gap: 1rem; }

.text-center { text-align: center; }
.text-right { text-align: right; }

.text-sm { font-size: 0.875rem; }
.text-lg { font-size: 1.125rem; }
.text-xl { font-size: 1.25rem; }

.font-bold { font-weight: 700; }
.font-semibold { font-weight: 600; }

.text-gray-600 { color: var(--gray-600); }
.text-danger { color: var(--danger); }

/* Page Header */
.page-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 2rem;
  padding-top: 2rem;
}

.page-title {
  font-size: 2rem;
  font-weight: 700;
  color: var(--gray-900);
}

/* Responsive */
@media (max-width: 768px) {
  .nav-menu {
    flex-direction: column;
    gap: 0.5rem;
  }
  
  .stats-grid {
    grid-template-columns: 1fr;
  }
  
  .page-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 1rem;
  }
  
  table {
    font-size: 0.875rem;
  }
  
  th, td {
    padding: 0.75rem 0.5rem;
  }
}