:root { 
            --accent-color: #4a148c;
            --light-gray: #f8f9fa;
            --border-color: #eaeaea;
            --text-color: #333;
            --text-muted: #6c757d;
            --success-color: #28a745;
            --warning-color: #ffc107;
        }
         .page-header {
            background: linear-gradient(135deg, rgba(199, 125, 255, 0.4) 0%, rgba(123, 44, 191, 0.4) 100%);
            padding: 1.5rem 0;
            margin-bottom: 2rem;
            border-bottom: 1px solid rgba(123, 44, 191, 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);
        }
        .color-preview-large {
            width: 100%;
            height: 120px;
            border-radius: 8px;
            border: 2px solid #ddd;
            margin-bottom: 1.5rem;
            background-color: #ff0000;
            transition: background-color 0.1s;
            cursor: pointer;
        }
        .example-buttons {
            display: flex;
            flex-wrap: wrap;
            gap: 0.5rem;
            margin: 1rem 0;
        }
        .example-btn {
            background-color: rgba(123, 44, 191, 0.1);
            border: 1px solid rgba(123, 44, 191, 0.2);
            border-radius: 4px;
            padding: 0.5rem 0.75rem;
            font-size: 0.9rem;
            color: var(--primary-color);
            cursor: pointer;
            transition: all 0.2s;
            font-family: 'Courier New', monospace;
        }
        .example-btn:hover {
            background-color: rgba(123, 44, 191, 0.2);
            transform: translateY(-2px);
        }
        .nav-tabs .nav-tabs .tab-content {
            padding: 1.5rem 0;
        }
        .color-wheel-container {
            display: flex;
            justify-content: center;
            margin: 1rem 0;
        }
        #colorWheel {
            width: 260px;
            height: 260px;
            border-radius: 50%;
            box-shadow: 0 4px 12px rgba(0,0,0,0.15);
            cursor: crosshair;
        }
        .image-picker-area {
            border: 2px dashed var(--border-color);
            border-radius: 8px;
            padding: 1.5rem;
            text-align: center;
            background-color: var(--light-gray);
            cursor: pointer;
            transition: background-color 0.3s;
        }
        .image-picker-area:hover {
            background-color: #e9ecef;
        }
        .image-picker-area i {
            font-size: 2.5rem;
            color: var(--primary-color);
            margin-bottom: 0.5rem;
        }
        #imageUpload {
            display: none;
        }
        .image-preview-container {
            position: relative;
            margin-top: 1rem;
            display: none;
            max-width: 100%;
            overflow-x: auto;
        }
        #imagePreview {
            max-width: 100%;
            border-radius: 4px;
            border: 1px solid var(--border-color);
            cursor: crosshair;
        }
        .pixel-coords {
            background-color: rgba(0,0,0,0.7);
            color: white;
            padding: 0.25rem 0.75rem;
            border-radius: 20px;
            font-size: 0.9rem;
            display: inline-block;
            margin-top: 0.5rem;
        }
        .harmony-swatch {
            width: 100%;
            height: 60px;
            border-radius: 4px;
            border: 1px solid #ddd;
            margin-bottom: 0.5rem;
        }
        .harmony-label {
            font-size: 0.85rem;
            color: var(--text-muted);
            text-align: center;
        }
        .derivative-table {
            width: 100%;
            border-collapse: collapse;
            margin: 1.5rem 0;
        }
        .derivative-table th, .derivative-table td {
            padding: 0.75rem;
            text-align: left;
            border: 1px solid var(--border-color);
        }
        .derivative-table th {
            background-color: var(--light-gray);
            font-weight: 600;
        }
        @media (max-width: 768px) {
            }