:root {
    --primary-color: #3498db;
    --secondary-color: #2ecc71;
    --danger-color: #e74c3c;
    --dark-color: #2c3e50;
    --light-color: #ecf0f1;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f8f9fa;
}

.sidebar {
    background-color: var(--dark-color);
    min-height: 100vh;
    color: white;
}

.sidebar .nav-link {
    color: rgba(255, 255, 255, 0.8);
    border-radius: 5px;
    margin-bottom: 5px;
}

.sidebar .nav-link:hover, .sidebar .nav-link.active {
    background-color: rgba(255, 255, 255, 0.1);
    color: white;
}

.sidebar .nav-link i {
    margin-right: 10px;
}

.main-content {
    padding: 20px;
}

.card {
    border: none;
    border-radius: 10px;
    box-shadow: 0 0 15px rgba(0, 0, 0, 0.05);
    margin-bottom: 20px;
}

.card-header {
    background-color: white;
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
    font-weight: 600;
}

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

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

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

.table th {
    border-top: none;
    font-weight: 600;
    color: var(--dark-color);
}

.badge {
    font-weight: 500;
    padding: 5px 10px;
}

.alert {
    border-radius: 8px;
}

/* Dashboard stats */
.stat-card {
    border-left: 4px solid;
    border-radius: 8px;
}

.stat-card.primary {
    border-left-color: var(--primary-color);
}

.stat-card.success {
    border-left-color: var(--secondary-color);
}

.stat-card.danger {
    border-left-color: var(--danger-color);
}

/* Responsive adjustments */
@media (max-width: 768px) {
    .sidebar {
        min-height: auto;
    }
    
    .main-content {
        padding: 15px;
    }
}