:root {
    --primary-color: #007bff;
    --secondary-color: #6c757d;
    --success-color: #28a745;
    --danger-color: #dc3545;
    --warning-color: #ffc107;
    --info-color: #17a2b8;
    --light-color: #f8f9fa;
    --dark-color: #343a40;
}

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

.login-body {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.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);
    background-color: #343a40;
}

.sidebar-sticky {
    position: relative;
    top: 0;
    height: calc(100vh - 48px);
    padding-top: .5rem;
    overflow-x: hidden;
    overflow-y: auto;
}

.sidebar .nav-link {
    color: #fff;
    padding: 0.75rem 1rem;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}

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

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

.card {
    border: none;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    transition: transform 0.2s;
}

.card:hover {
    transform: translateY(-2px);
}

.badge {
    font-size: 0.75em;
    padding: 0.5em 0.75em;
}

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

.btn {
    border-radius: 6px;
    font-weight: 500;
}

.modal-content {
    border-radius: 10px;
    border: none;
}

.alert {
    border-radius: 8px;
    border: none;
}
.alert2 {
    border-radius: 8px;
    border: none;
}

/* Responsive adjustments */
@media (max-width: 768px) {
    .sidebar {
        position: static;
        height: auto;
    }
    
    .sidebar-sticky {
        height: auto;
    }
}

/* Dark Mode */
body.dark-mode {
    background-color: #1a1a1a;
    color: #e0e0e0;
}

body.dark-mode .card {
    background-color: #2d2d2d;
    color: #e0e0e0;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
}

body.dark-mode .table {
    color: #e0e0e0;
}

body.dark-mode .table-striped tbody tr:nth-of-type(odd) {
    background-color: rgba(255, 255, 255, 0.05);
}

body.dark-mode .form-control {
    background-color: #3d3d3d;
    border-color: #4d4d4d;
    color: #e0e0e0;
}

body.dark-mode .form-control:focus {
    background-color: #3d3d3d;
    border-color: #007bff;
    color: #e0e0e0;
}

body.dark-mode .modal-content {
    background-color: #2d2d2d;
    color: #e0e0e0;
}

body.dark-mode .sidebar {
    background-color: #252525;
}

/* Dark Mode Toggle Button */
.theme-toggle {
    background: none;
    border: none;
    color: inherit;
    cursor: pointer;
    font-size: 1.2rem;
    padding: 0.5rem;
    border-radius: 50%;
    transition: background-color 0.3s;
}

.theme-toggle:hover {
    background-color: rgba(255, 255, 255, 0.1);
}