:root {
            --primary-color: #2c7da0;
            --secondary-color: #a9d6e5;
            --accent-color: #01497c;
            --light-gray: #f8f9fa;
            --border-color: #eaeaea;
            --text-color: #333;
            --text-muted: #6c757d;
            --success-color: #28a745;
            --warning-color: #ffc107;
            --danger-color: #dc3545;
        }
         
        .page-header {
            background: linear-gradient(135deg, rgba(169, 214, 229, 0.4) 0%, rgba(44, 125, 160, 0.4) 100%);
            padding: 1.5rem 0;
            margin-bottom: 2rem;
            border-bottom: 1px solid rgba(44, 125, 160, 0.2);
            position: relative;
            overflow: hidden;      color: var(--text-color);
        }
         
        .breadcrumb {
            background-color: transparent;
            padding: 0.5rem 0;
            margin-bottom: 0.5rem;
        }
        
        .breadcrumb-item a {
            color: var(--text-muted);
            text-decoration: none;
        }
        
        .breadcrumb-item.active {
            color: var(--text-color);
        }
         
        /* Simulation Controls */
        .simulation-controls {
            display: flex;
            justify-content: center;
            gap: 1rem;
            margin: 1rem 0;
            flex-wrap: wrap;
        }
 
        /* Stats Container */
        .stats-container {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 1rem;
            margin: 1.5rem 0;
        }
        
        .stat-card {
            background: white;
            border-radius: 8px;
            padding: 1.25rem;
            border: 1px solid var(--border-color);
            box-shadow: 0 2px 4px rgba(0,0,0,0.05);
            text-align: center;
        }
        
        .stat-value {
            font-size: 1.75rem;
            font-weight: 700;
            color: var(--primary-color);
            margin-bottom: 0.5rem;
        }
        
        .stat-label {
            color: var(--text-muted);
            font-size: 0.9rem;
        }
         
        /* Responsive Adjustments */
        @media (max-width: 768px) { 
            .stats-container {
                grid-template-columns: 1fr 1fr;
            }
            
            .simulation-controls {
                flex-direction: column;
                align-items: center;
            }
        }
         
        /* Allele frequency display */
        .allele-frequency {
            display: flex;
            align-items: center;
            margin-bottom: 1rem;
        }
        
        .allele-label {
            width: 100px;
            font-weight: 600;
        }
        
        .allele-bar {
            flex-grow: 1;
            height: 20px;
            background-color: #e9ecef;
            border-radius: 4px;
            overflow: hidden;
            margin: 0 1rem;
        }
        
        .allele-fill {
            height: 100%;
            transition: width 0.5s ease;
        }
        
        .allele-a-fill {
            background-color: #2c7da0;
        }
        
        .allele-b-fill {
            background-color: #e67700;
        }
        
        .allele-value {
            width: 60px;
            text-align: right;
            font-weight: 600;
        }
        
        /* Generation counter */
        .generation-counter {
            background: rgba(255, 255, 255, 0.9);
            padding: 8px 16px;
            border-radius: 4px;
            font-weight: 600;
            color: var(--primary-color);
            margin-bottom: 1rem;
            display: inline-block;
        }
        
        /* Multiple simulation results */
        .simulation-results {
            margin-top: 2rem;
        }
        
        .simulation-run {
            margin-bottom: 2rem;
            padding-bottom: 1rem;
            border-bottom: 1px solid var(--border-color);
        }
        
        /* Speed control */
        .speed-control {
            display: flex;
            align-items: center;
            margin: 1rem 0;
        }
        
        .speed-label {
            margin-right: 1rem;
            font-weight: 600;
        }
        
        /* Model selection */
        .model-selection {
            display: flex;
            gap: 1rem;
            margin-bottom: 1rem;
        }
        
        .model-btn {
            flex: 1;
            text-align: center;
            padding: 0.75rem;
            border-radius: 4px;
            cursor: pointer;
            transition: all 0.3s;
            font-weight: 600;
            border: 1px solid var(--border-color);
            background-color: var(--light-gray);
        }
        
        .model-btn.active {
            background-color: var(--primary-color);
            color: white;
            border-color: var(--primary-color);
        }
        
        /* Small chart container */
        .chart-container-small {
            height: 200px;
            width: 100%;
        }
        
        /* Progress bar */
        .progress-container {
            margin: 1rem 0;
        }
        
        .progress-label {
            display: flex;
            justify-content: between;
            margin-bottom: 0.5rem;
        }
        
        .export-controls {
            display: flex;
            justify-content: flex-end;
            gap: 0.5rem;
            margin-top: 1rem;
        }
        
        .additional-stats {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
            gap: 1rem;
            margin-top: 1rem;
        }
        
        .additional-stat-card {
            background: rgba(44, 125, 160, 0.05);
            border-radius: 6px;
            padding: 1rem;
            text-align: center;
        }
        
        .additional-stat-value {
            font-size: 1.25rem;
            font-weight: 600;
            color: var(--primary-color);
        }
        
        .additional-stat-label {
            color: var(--text-muted);
            font-size: 0.85rem;
        }