:root {
    --primary-color: #0d6efd;
    --secondary-color: #6c757d;
    --success-color: #198754;
    --danger-color: #dc3545;
    --warning-color: #ffc107;
    --info-color: #0dcaf0;
    --light-color: #f8f9fa;
    --dark-color: #212529;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f5f5f5;
}

.sidebar {
    position: fixed;
    top: 0;
    bottom: 0;
    left: 0;
    z-index: 100;
    padding: 48px 0 0;
    box-shadow: inset -1px 0 0 rgba(0, 0, 0, .1);
}

.sidebar .nav-link {
    font-weight: 500;
    color: #333;
    padding: 0.5rem 1rem;
    margin: 0.2rem 0;
    border-radius: 0.25rem;
}

.sidebar .nav-link:hover {
    color: var(--primary-color);
    background-color: rgba(13, 110, 253, 0.1);
}

.sidebar .nav-link.active {
    color: var(--primary-color);
    background-color: rgba(13, 110, 253, 0.1);
}

.sidebar .nav-link i {
    margin-right: 0.5rem;
    width: 1.25rem;
    text-align: center;
}

main {
    padding-top: 1.5rem;
}

.table th {
    font-weight: 600;
    background-color: #f8f9fa;
}

.table td {
    vertical-align: middle;
}

.btn-sm {
    padding: 0.25rem 0.5rem;
    font-size: 0.875rem;
}

.modal-header {
    background-color: #f8f9fa;
    border-bottom: 1px solid #dee2e6;
}

.modal-footer {
    background-color: #f8f9fa;
    border-top: 1px solid #dee2e6;
}

.form-label {
    font-weight: 500;
}

.form-select, .form-control {
    border-radius: 0.25rem;
}

.form-select:focus, .form-control:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 0.25rem rgba(13, 110, 253, 0.25);
}

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

.btn-primary:hover {
    background-color: #0b5ed7;
    border-color: #0a58ca;
}

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

.btn-danger:hover {
    background-color: #bb2d3b;
    border-color: #b02a37;
}

.alert {
    border-radius: 0.25rem;
    margin-bottom: 1rem;
}

.alert-success {
    background-color: rgba(25, 135, 84, 0.1);
    border-color: rgba(25, 135, 84, 0.2);
    color: var(--success-color);
}

.alert-danger {
    background-color: rgba(220, 53, 69, 0.1);
    border-color: rgba(220, 53, 69, 0.2);
    color: var(--danger-color);
}

.alert-warning {
    background-color: rgba(255, 193, 7, 0.1);
    border-color: rgba(255, 193, 7, 0.2);
    color: var(--warning-color);
}

.alert-info {
    background-color: rgba(13, 202, 240, 0.1);
    border-color: rgba(13, 202, 240, 0.2);
    color: var(--info-color);
}