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

:root {
  --primary: #667eea;
  --primary-dark: #5568d3;
  --secondary: #764ba2;
  --success: #10b981;
  --danger: #ef4444;
  --warning: #f59e0b;
  --info: #3b82f6;
  --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;
  --radius: 0.5rem;
  --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);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  color: var(--gray-900);
  background: var(--gray-50);
  line-height: 1.6;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.2;
  color: var(--gray-900);
}

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; }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.625rem 1.25rem;
  border: none;
  border-radius: var(--radius);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
  text-decoration: none;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

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

.btn-primary:hover:not(:disabled) {
  background: var(--primary-dark);
}

.btn-secondary {
  background: var(--gray-200);
  color: var(--gray-800);
}

.btn-secondary:hover:not(:disabled) {
  background: var(--gray-300);
}

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

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

.btn-outline {
  background: transparent;
  border: 1px solid var(--gray-300);
  color: var(--gray-700);
}

.btn-outline:hover:not(:disabled) {
  background: var(--gray-100);
}

.btn-sm {
  padding: 0.375rem 0.875rem;
  font-size: 0.8125rem;
}

.btn-lg {
  padding: 0.875rem 1.75rem;
  font-size: 1rem;
}

/* Forms */
.form-group {
  margin-bottom: 1.25rem;
}

label {
  display: block;
  margin-bottom: 0.5rem;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--gray-700);
}

input[type="text"],
input[type="email"],
input[type="password"],
input[type="number"],
input[type="date"],
textarea,
select {
  width: 100%;
  padding: 0.625rem 0.875rem;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius);
  font-size: 0.875rem;
  transition: border-color 0.2s;
}

input:focus,
textarea:focus,
select:focus {
  outline: none;
  border-color: var(--primary);
}

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

.form-error {
  color: var(--danger);
  font-size: 0.8125rem;
  margin-top: 0.25rem;
}

/* Cards */
.card {
  background: white;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.card-header {
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--gray-200);
}

.card-body {
  padding: 1.5rem;
}

.card-footer {
  padding: 1.25rem 1.5rem;
  border-top: 1px solid var(--gray-200);
  background: var(--gray-50);
}

/* Badges */
.badge {
  display: inline-block;
  padding: 0.25rem 0.625rem;
  border-radius: 9999px;
  font-size: 0.75rem;
  font-weight: 500;
}

.badge-primary { background: var(--primary); color: white; }
.badge-success { background: var(--success); color: white; }
.badge-warning { background: var(--warning); color: white; }
.badge-danger { background: var(--danger); color: white; }
.badge-gray { background: var(--gray-200); color: var(--gray-700); }

/* Tables */
.table {
  width: 100%;
  border-collapse: collapse;
}

.table th,
.table td {
  padding: 0.75rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--gray-200);
}

.table th {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--gray-700);
  text-transform: uppercase;
  letter-spacing: 0.025em;
  background: var(--gray-50);
}

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

/* Alerts */
.alert {
  padding: 1rem 1.25rem;
  border-radius: var(--radius);
  margin-bottom: 1rem;
}

.alert-success {
  background: #d1fae5;
  border-left: 4px solid var(--success);
  color: #065f46;
}

.alert-danger {
  background: #fee2e2;
  border-left: 4px solid var(--danger);
  color: #991b1b;
}

.alert-warning {
  background: #fef3c7;
  border-left: 4px solid var(--warning);
  color: #92400e;
}

.alert-info {
  background: #dbeafe;
  border-left: 4px solid var(--info);
  color: #1e40af;
}

/* Utilities */
.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.text-center { text-align: center; }
.text-right { text-align: right; }
.text-muted { color: var(--gray-600); }
.text-sm { font-size: 0.875rem; }
.text-xs { font-size: 0.75rem; }

.mt-1 { margin-top: 0.25rem; }
.mt-2 { margin-top: 0.5rem; }
.mt-3 { margin-top: 1rem; }
.mt-4 { margin-top: 1.5rem; }
.mt-5 { margin-top: 2rem; }

.mb-1 { margin-bottom: 0.25rem; }
.mb-2 { margin-bottom: 0.5rem; }
.mb-3 { margin-bottom: 1rem; }
.mb-4 { margin-bottom: 1.5rem; }
.mb-5 { margin-bottom: 2rem; }

.grid {
  display: grid;
  gap: 1.5rem;
}

.grid-cols-2 {
  grid-template-columns: repeat(2, 1fr);
}

.grid-cols-3 {
  grid-template-columns: repeat(3, 1fr);
}

.grid-cols-4 {
  grid-template-columns: repeat(4, 1fr);
}

@media (max-width: 768px) {
  .grid-cols-2,
  .grid-cols-3,
  .grid-cols-4 {
    grid-template-columns: 1fr;
  }
}

.flex {
  display: flex;
}

.items-center {
  align-items: center;
}

.justify-between {
  justify-content: space-between;
}

.gap-2 { gap: 0.5rem; }
.gap-3 { gap: 1rem; }
.gap-4 { gap: 1.5rem; }

.loading {
  display: inline-block;
  width: 1.5rem;
  height: 1.5rem;
  border: 3px solid var(--gray-200);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

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