:root {
            --primary-color: #2c7da0;
            --secondary-color: #a9d6e5;
            --accent-color: #01497c;
            --success-color: #28a745;
            --warning-color: #ffc107;
            --info-color: #17a2b8;
            --math-color: #6f42c1;
            --regression-color: #e83e8c;
            --data-color: #fd7e14;
        }
 
        .form-control:focus {
            border-color: var(--primary-color);
            box-shadow: 0 0 0 3px rgba(44, 125, 160, 0.15);
        }
        .data-table-container {
            overflow-x: auto;
            margin-bottom: 1.5rem;
        }
        .data-table {
            width: 100%;
            border-collapse: collapse;
        }
        .data-table th {
            background-color: #f8f9fa;
            font-weight: 600;
            text-align: center;
            padding: 0.75rem;
            border: 1px solid #dee2e6;
        }
        .data-table td {
            padding: 0.5rem;
            border: 1px solid #dee2e6;
            text-align: center;
        }
        .data-table input {
            width: 100%;
            border: 1px solid #ddd;
            border-radius: 4px;
            padding: 0.375rem 0.5rem;
            text-align: center;
        }
        .data-point-badge {
            display: inline-block;
            background-color: rgba(44, 125, 160, 0.1);
            color: var(--primary-color);
            padding: 0.25rem 0.5rem;
            border-radius: 4px;
            font-size: 0.85rem;
            margin: 0.25rem;
            font-family: 'Courier New', monospace;
        }
        .import-section {
            background-color: #f8f9fa;
            border-radius: 6px;
            padding: 1.5rem;
            margin-bottom: 1.5rem;
            border: 1px dashed #adb5bd;
        }
        .import-options {
            display: flex;
            flex-wrap: wrap;
            gap: 1rem;
            margin-bottom: 1rem;
        }
        .import-option {
            flex: 1;
            min-width: 150px;
            text-align: center;
            padding: 1rem;
            border: 2px solid #eaeaea;
            border-radius: 6px;
            cursor: pointer;
            transition: all 0.3s;
        }
        .import-option:hover {
            border-color: var(--primary-color);
            background-color: rgba(44, 125, 160, 0.05);
        }
        .import-option.active {
            border-color: var(--primary-color);
            background-color: rgba(44, 125, 160, 0.1);
        }
        .import-icon {
            font-size: 2rem;
            margin-bottom: 0.5rem;
            color: var(--primary-color);
        }
        .import-content {
            display: none;
        }
        .import-content.active {
            display: block;
        }
        .data-preview {
            max-height: 200px;
            overflow-y: auto;
            background-color: white;
            border: 1px solid #dee2e6;
            border-radius: 4px;
            padding: 1rem;
            margin-top: 1rem;
            font-family: monospace;
            white-space: pre-wrap;
        }
        .preview-table {
            width: 100%;
            border-collapse: collapse;
            margin-top: 1rem;
        }
        .preview-table th, .preview-table td {
            padding: 0.5rem;
            border: 1px solid #dee2e6;
            text-align: center;
        }
        .preview-table th {
            background-color: #f8f9fa;
        }
        .regression-options {
            display: flex;
            flex-wrap: wrap;
            gap: 0.5rem;
            margin: 1rem 0;
        }
        .regression-option {
            padding: 0.75rem 1.25rem;
            border: 2px solid #eaeaea;
            border-radius: 6px;
            background-color: white;
            cursor: pointer;
            transition: all 0.3s;
            text-align: center;
            flex: 1;
            min-width: 120px;
        }
        .regression-option:hover {
            border-color: var(--primary-color);
            background-color: rgba(44, 125, 160, 0.05);
        }
        .regression-option.active {
            border-color: var(--primary-color);
            background-color: rgba(44, 125, 160, 0.1);
            font-weight: 600;
        }
        .regression-icon {
            font-size: 1.5rem;
            margin-bottom: 0.5rem;
            color: var(--primary-color);
        }
        .equation-container {
            padding: 12px;
            background-color: white;
            border-radius: 4px;
            border: 1px solid #eee;
            font-size: 1.1rem;
            margin: 10px 0;
            text-align: center;
        }
        .equation-box {
            font-size: 1.3rem;
            padding: 15px;
            background-color: rgba(111, 66, 193, 0.05);
            border-left: 4px solid var(--math-color);
            border-radius: 4px;
            margin: 15px 0;
            font-family: 'Cambria Math', 'Latin Modern Math', STIXGeneral, serif;
        }
        .stats-container {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
            gap: 1rem;
            margin: 1.5rem 0;
        }
        .stat-card {
            background: white;
            border-radius: 8px;
            padding: 1.25rem;
            border: 1px solid #eaeaea;
            text-align: center;
        }
        .stat-value {
            font-size: 1.75rem;
            font-weight: 700;
            color: var(--primary-color);
            margin-bottom: 0.5rem;
        }
        .stat-label {
            color: #6c757d;
            font-size: 0.9rem;
            font-weight: 600;
        }
        .residuals-container {
            height: 200px;
            width: 100%;
            margin: 1.5rem 0;
        }
        @media (max-width: 768px) {
            .stats-container {
                grid-template-columns: 1fr;
            }
            .regression-option {
                min-width: 100px;
            }
            .import-option {
                min-width: 120px;
            }
        }
        .data-examples {
            display: flex;
            flex-wrap: wrap;
            gap: 0.5rem;
            margin: 1rem 0;
        }
        .example-btn {
            background-color: rgba(44, 125, 160, 0.1);
            border: 1px solid rgba(44, 125, 160, 0.2);
            border-radius: 4px;
            padding: 0.5rem 0.75rem;
            font-size: 0.9rem;
            color: var(--primary-color);
            cursor: pointer;
            transition: all 0.2s;
        }
        .example-btn:hover {
            background-color: rgba(44, 125, 160, 0.2);
            transform: translateY(-2px);
        }
        .graph-legend {
            display: flex;
            justify-content: center;
            flex-wrap: wrap;
            gap: 1.5rem;
            margin-top: 1rem;
        }
        .legend-item {
            display: flex;
            align-items: center;
        }
        .legend-color {
            width: 20px;
            height: 4px;
            margin-right: 0.5rem;
        }
        .data-color {
            width: 10px;
            height: 10px;
            border-radius: 50%;
            margin-right: 0.5rem;
            background-color: rgba(253, 126, 20, 0.8);
        }
        .regression-color {
            background-color: rgba(232, 62, 140, 0.8);
        }
        .residuals-table {
            width: 100%;
            border-collapse: collapse;
            margin: 1rem 0;
        }
        .residuals-table th, .residuals-table td {
            padding: 0.5rem;
            text-align: center;
            border: 1px solid #dee2e6;
        }
        .residuals-table th {
            background-color: #f8f9fa;
            font-weight: 600;
        }
        .file-upload-area {
            border: 2px dashed #adb5bd;
            border-radius: 6px;
            padding: 2rem;
            text-align: center;
            cursor: pointer;
            transition: all 0.3s;
            margin-bottom: 1rem;
        }
        .file-upload-area:hover {
            border-color: var(--primary-color);
            background-color: rgba(44, 125, 160, 0.05);
        }
        .file-upload-area.dragover {
            border-color: var(--primary-color);
            background-color: rgba(44, 125, 160, 0.1);
        }
        .file-upload-icon {
            font-size: 3rem;
            color: var(--primary-color);
            margin-bottom: 1rem;
        }