:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --success: #10b981;
    --danger: #ef4444;
    --warning: #f59e0b;
    --dark: #1f2937;
    --light: #f9fafb;
    --border: #e5e7eb;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--light);
    color: var(--dark);
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

.navbar {
    background: white;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    padding: 1rem 0;
    margin-bottom: 2rem;
}

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

.navbar h1 {
    color: var(--primary);
    font-size: 1.5rem;
}

.nav-links {
    display: flex;
    gap: 1.5rem;
    list-style: none;
}

.nav-links a {
    color: var(--dark);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
}

.nav-links a:hover {
    color: var(--primary);
}

.card {
    background: white;
    border-radius: 12px;
    padding: 2rem;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    margin-bottom: 1.5rem;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: white;
    border-radius: 12px;
    padding: 1.5rem;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    border-left: 4px solid var(--primary);
}

.stat-card h3 {
    font-size: 0.875rem;
    color: #6b7280;
    margin-bottom: 0.5rem;
    text-transform: uppercase;
}

.stat-card .value {
    font-size: 2rem;
    font-weight: bold;
    color: var(--dark);
}

.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
    font-size: 1rem;
}

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

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

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

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

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

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--dark);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.75rem;
    border: 2px solid var(--border);
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.3s;
}

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

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

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

.table th {
    background: var(--light);
    font-weight: 600;
    color: var(--dark);
}

.table tr:hover {
    background: var(--light);
}

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

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

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

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

.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    z-index: 1000;
    align-items: center;
    justify-content: center;
}

.modal.active {
    display: flex;
}

.modal-content {
    background: white;
    border-radius: 12px;
    padding: 2rem;
    max-width: 500px;
    width: 90%;
    max-height: 90vh;
    overflow-y: auto;
}

.loading {
    text-align: center;
    padding: 2rem;
}

.spinner {
    border: 4px solid var(--border);
    border-top: 4px solid var(--primary);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
    margin: 0 auto;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}