: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;
            -tetris-i: #00bcd4;
            --tetris-o: #ffeb3b;
            --tetris-t: #9c27b0;
            --tetris-s: #4caf50;
            --tetris-z: #f44336;
            --tetris-j: #2196f3;
            --tetris-l: #ff9800;
            --game-bg: #0d1520;
            /* Tetris block colors */
            --block-i: #00f0f0; /* Cyan */
            --block-j: #0000f0; /* Blue */
            --block-l: #f0a000; /* Orange */
            --block-o: #f0f000; /* Yellow */
            --block-s: #00f000; /* Green */
            --block-t: #a000f0; /* Purple */
            --block-z: #f00000; /* Red */
            --block-empty: #1a1a2e; /* Dark blue for empty cells */
            --grid-line: #2d3047;
        }
        .tetris-piece-display {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    margin: 1.5rem 0;
    justify-content: center;
}.piece-example {
    width: 80px;
    height: 80px;
    background-color: #000;
    border-radius: 6px;
    border: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}.piece-example canvas {
    width: 60px;
    height: 60px;
}.piece-name {
    position: absolute;
    bottom: -20px;
    font-size: 0.8rem;
    font-weight: 500;
    color: var(--text-color);
}
  
        .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);
        }
         
        .game-area {
            display: flex;
            flex-direction: column;
            align-items: center;
            margin: 2rem 0;
        }
        
        .tetris-game-container {
            display: flex;
            flex-wrap: wrap;
            justify-content: center;
            gap: 2rem;
            width: 100%;
            max-width: 1000px;
            margin: 0 auto;
        }
        
        .tetris-main-game {
            display: flex;
            flex-direction: column;
            align-items: center;
        }
        
        .tetris-grid-container {
            width: 300px;
            height: 600px;
            background-color: var(--block-empty);
            border: 2px solid var(--grid-line);
            border-radius: 4px;
            overflow: hidden;
            position: relative;
            box-shadow: 0 4px 12px rgba(0,0,0,0.1);
        }
        
        #tetrisGrid {
            display: grid;
            grid-template-columns: repeat(10, 1fr);
            grid-template-rows: repeat(20, 1fr);
            width: 100%;
            height: 100%;
            gap: 1px;
            background-color: var(--grid-line);
        }
        
        .tetris-cell {
            background-color: var(--block-empty);
            border: 1px solid rgba(255, 255, 255, 0.05);
            transition: background-color 0.1s;
        }
        
        .tetris-cell.filled {
            border: none;
            box-shadow: inset 0 0 10px rgba(0,0,0,0.3);
        }
        
        /* Tetromino colors */
        .tetris-cell.i { background-color: var(--block-i); }
        .tetris-cell.j { background-color: var(--block-j); }
        .tetris-cell.l { background-color: var(--block-l); }
        .tetris-cell.o { background-color: var(--block-o); }
        .tetris-cell.s { background-color: var(--block-s); }
        .tetris-cell.t { background-color: var(--block-t); }
        .tetris-cell.z { background-color: var(--block-z); }
        
        .tetris-side-panel {
            display: flex;
            flex-direction: column;
            gap: 1.5rem;
            width: 250px;
        }
         
        .game-stats {
            display: flex;
            justify-content: space-between;  
            align-items: center;
            background-color: var(--light-gray);
            border-radius: 8px;
            padding: 1.5rem;
            border: 1px solid var(--border-color);
            gap: 1rem;
            flex-wrap: wrap;  
        }
        
        .stat-item {
            display: flex;
            flex-direction: column;
            align-items: center;
            flex: 1;  
            min-width: 100px; 
            padding: 0.5rem;
        }
        
        .stat-label {
            color: var(--text-muted);
            font-size: 0.9rem;
            margin-bottom: 0.5rem;
            text-align: center;
        }
        
        .stat-value {
            font-size: 1.8rem;  
            font-weight: 700;
            color: var(--primary-color);
            text-align: center;
        }
        
        .next-piece-container {
            background-color: var(--light-gray);
            border-radius: 8px;
            padding: 1.5rem;
            border: 1px solid var(--border-color);
            text-align: center;
        }
        
        .next-piece-title {
            font-weight: 600;
            margin-bottom: 1rem;
            color: var(--primary-color);
        }
        
        .next-piece-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            grid-template-rows: repeat(4, 1fr);
            width: 120px;
            height: 120px;
            margin: 0 auto;
            gap: 2px;
            background-color: var(--block-empty);
            border: 2px solid var(--grid-line);
            border-radius: 4px;
            overflow: hidden; 
        }
        
        .next-cell {
            background-color: var(--block-empty);
            border: 1px solid rgba(255, 255, 255, 0.05);
        }
        
        .next-cell.filled {
            border: none;
            box-shadow: inset 0 0 5px rgba(0,0,0,0.3);
        }
 
        .next-cell.i { background-color: var(--block-i); }
        .next-cell.j { background-color: var(--block-j); }
        .next-cell.l { background-color: var(--block-l); }
        .next-cell.o { background-color: var(--block-o); }
        .next-cell.s { background-color: var(--block-s); }
        .next-cell.t { background-color: var(--block-t); }
        .next-cell.z { background-color: var(--block-z); }
        
        .game-controls {
            display: flex;
            flex-wrap: wrap;
            justify-content: center;
            gap: 1rem;
            margin: 1.5rem 0;
        }
        
        .game-btn {
            padding: 0.75rem 1.5rem;
            border-radius: 6px;
            font-weight: 600;
            transition: all 0.3s;
            border: none;
            cursor: pointer;
            display: flex;
            align-items: center;
            justify-content: center;
            min-width: 120px;
        }
        
        .game-btn-primary {
            background-color: var(--primary-color);
            color: white;
        }
        
        .game-btn-primary:hover {
            background-color: var(--accent-color);
            transform: translateY(-2px);
        }
        
        .game-btn-secondary {
            background-color: #6c757d;
            color: white;
        }
        
        .game-btn-secondary:hover {
            background-color: #5a6268;
            transform: translateY(-2px);
        }
        
        .game-btn-success {
            background-color: var(--success-color);
            color: white;
        }
        
        .game-btn-success:hover {
            background-color: #218838;
            transform: translateY(-2px);
        }
        
        .game-btn-warning {
            background-color: var(--warning-color);
            color: #212529;
        }
        
        .game-btn-warning:hover {
            background-color: #e0a800;
            transform: translateY(-2px);
        }
        
        .game-btn-danger {
            background-color: var(--danger-color);
            color: white;
        }
        
        .game-btn-danger:hover {
            background-color: #c82333;
            transform: translateY(-2px);
        }
        
        .game-info-box {
            background-color: rgba(44, 125, 160, 0.05);
            border-left: 3px solid var(--primary-color);
            padding: 1rem;
            border-radius: 0 4px 4px 0;
            margin: 1.5rem 0;
        }
        
        .game-tip-box {
            background-color: rgba(255, 193, 7, 0.05);
            border-left: 3px solid var(--warning-color);
            padding: 1rem;
            border-radius: 0 4px 4px 0;
            margin: 1.5rem 0;
        }
        
        .victory-message {
            background: linear-gradient(135deg, rgba(40, 167, 69, 0.1) 0%, rgba(40, 167, 69, 0.3) 100%);
            border: 2px solid var(--success-color);
            border-radius: 8px;
            padding: 2rem;
            text-align: center;
            margin: 2rem 0;
            display: none;
        }
        
        .victory-title {
            font-size: 2rem;
            font-weight: 700;
            color: var(--success-color);
            margin-bottom: 1rem;
        }
        
        .game-over-message {
            background: linear-gradient(135deg, rgba(220, 53, 69, 0.1) 0%, rgba(220, 53, 69, 0.3) 100%);
            border: 2px solid var(--danger-color);
            border-radius: 8px;
            padding: 2rem;
            text-align: center;
            margin: 2rem 0;
            display: none;
        }
        
        .game-over-title {
            font-size: 2rem;
            font-weight: 700;
            color: var(--danger-color);
            margin-bottom: 1rem;
        }
        
        .level-selection {
            display: flex;
            flex-wrap: wrap;
            gap: 0.25rem;
            margin: 1.5rem 0;
        }
        
        .level-btn {
            padding: 0.25rem;
            border-radius: 6px;
            font-weight: 600;
            background-color: white;
            border: 2px solid var(--border-color);
            transition: all 0.3s;
            cursor: pointer;
        }
        
        .level-btn:hover {
            background-color: var(--light-gray);
        }
        
        .level-btn.active {
            background-color: var(--primary-color);
            color: white;
            border-color: var(--primary-color);
        }
        
        /* 新增: 速度控制样式 */
        .speed-controls {
            display: flex;
            flex-wrap: wrap;
            gap: 0.5rem;
            margin: 1rem 0;
            justify-content: center;
        }
        
        .speed-btn {
            padding: 0.5rem 1rem;
            border-radius: 4px;
            font-weight: 600;
            background-color: white;
            border: 2px solid var(--border-color);
            transition: all 0.3s;
            cursor: pointer;
        }
        
        .speed-btn:hover {
            background-color: var(--light-gray);
        }
        
        .speed-btn.active {
            background-color: var(--primary-color);
            color: white;
            border-color: var(--primary-color);
        }
        
        .control-instructions {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
            gap: 1rem;
            margin: 1.5rem 0;
        }
        
        .control-item {
            background: white;
            border-radius: 8px;
            padding: 1rem;
            border: 1px solid var(--border-color);
            box-shadow: 0 2px 4px rgba(0,0,0,0.05);
            text-align: center;
        }
        
        .control-icon {
            font-size: 1.5rem;
            color: var(--primary-color);
            margin-bottom: 0.5rem;
        }
        
        .control-label {
            font-weight: 600;
            margin-bottom: 0.25rem;
        }
        
        .control-desc {
            color: var(--text-muted);
            font-size: 0.9rem;
        }
        
        .difficulty-indicator {
            display: inline-block;
            padding: 0.25rem 0.75rem;
            border-radius: 20px;
            font-size: 0.85rem;
            font-weight: 500;
            margin-right: 0.5rem;
        }
        
        .difficulty-easy {
            background-color: rgba(40, 167, 69, 0.1);
            color: #28a745;
        }
        
        .difficulty-medium {
            background-color: rgba(255, 193, 7, 0.1);
            color: #ffc107;
        }
        
        .difficulty-hard {
            background-color: rgba(220, 53, 69, 0.1);
            color: #dc3545;
        }
       
        .strategy-tips {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
            gap: 1rem;
            margin: 1.5rem 0;
        }
        
        .tip-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);
        }
        
        .tip-icon {
            width: 48px;
            height: 48px;
            border-radius: 8px;
            background-color: rgba(44, 125, 160, 0.1);
            display: flex;
            align-items: center;
            justify-content: center;
            margin-bottom: 1rem;
            color: var(--primary-color);
            font-size: 1.25rem;
        }
        
        .tip-title {
            font-weight: 600;
            margin-bottom: 0.5rem;
            color: var(--text-color);
        }
        
        .tip-desc {
            color: var(--text-muted);
            font-size: 0.9rem;
        }
        
        .high-scores-table {
            width: 100%;
            margin-bottom: 1rem;
        }
        
        .high-scores-table th {
            background-color: var(--light-gray);
            font-weight: 600;
            padding: 0.75rem;
            text-align: left;
        }
        
        .high-scores-table td {
            padding: 0.75rem;
            border-bottom: 1px solid var(--border-color);
        }
        
        .high-scores-table tr:nth-child(even) {
            background-color: rgba(0,0,0,0.02);
        }
        
        .mobile-controls {
            display: none;
            grid-template-columns: repeat(3, 1fr);
            grid-template-rows: repeat(2, 1fr);
            gap: 0.5rem;
            margin: 1.5rem 0;
            max-width: 300px;
        }
        
        .mobile-btn {
            padding: 1rem;
            background-color: var(--primary-color);
            color: white;
            border: none;
            border-radius: 8px;
            font-size: 1.5rem;
            display: flex;
            align-items: center;
            justify-content: center;
            cursor: pointer;
        }
        
        .mobile-btn:active {
            transform: scale(0.95);
        }
        
        .mobile-btn.rotate {
            grid-column: 2;
            grid-row: 1;
        }
        
        .mobile-btn.left {
            grid-column: 1;
            grid-row: 2;
        }
        
        .mobile-btn.down {
            grid-column: 2;
            grid-row: 2;
        }
        
        .mobile-btn.right {
            grid-column: 3;
            grid-row: 2;
        }
        
        .mobile-btn.pause {
            grid-column: 3;
            grid-row: 1;
        }
        
        @media (max-width: 768px) {
            .tool-card {
                padding: 1.5rem;
            }
            
            .tetris-game-container {
                flex-direction: column;
                align-items: center;
            }
            
            .tetris-grid-container {
                width: 250px;
                height: 500px;
            }
            
            .tetris-side-panel {
                width: 250px;
                flex-direction: row;
                flex-wrap: wrap;
                justify-content: center;
            }
            
            .next-piece-container {
                width: 150px;
            }
            
            .game-stats {
                flex-wrap: wrap;  
            }
            
            .stat-item {
                min-width: 45%; 
                margin-bottom: 0.5rem;
            }
            
            .game-controls {
                flex-direction: column;
                align-items: center;
            }
            
            .game-btn {
                width: 100%;
                max-width: 300px;
            }
            
            .mobile-controls {
                display: grid;
            }
        }
        
        @media (max-width: 480px) {
            .tetris-grid-container {
                width: 220px;
                height: 440px;
            }
            
            .tetris-side-panel {
                width: 220px;
            }
            
            .stat-item {
                min-width: 100%; 
            }
        }
         
        @keyframes pulse {
            0% { transform: scale(1); }
            50% { transform: scale(1.1); }
            100% { transform: scale(1); }
        }
        
        .pulse {
            animation: pulse 0.5s ease;
        }
        
        @keyframes lineClear {
            0% { background-color: inherit; }
            50% { background-color: white; }
            100% { background-color: inherit; }
        }
        
        .line-clearing {
            animation: lineClear 0.3s ease;
        }
        
        .btn {
            border-radius: 6px;
            padding: 0.75rem 1.5rem;
            font-weight: 600;
            transition: all 0.3s;
        }
        
        .btn-primary {
            background-color: var(--primary-color);
            border-color: var(--primary-color);
        }
        
        .btn-primary:hover {
            background-color: var(--accent-color);
            border-color: var(--accent-color);
            transform: translateY(-1px);
        }
        
        .btn-outline-primary {
            color: var(--primary-color);
            border-color: var(--primary-color);
        }
        
        .btn-outline-primary:hover {
            background-color: var(--primary-color);
            border-color: var(--primary-color);
            color: white;
        }
        
        .btn-outline-secondary {
            color: #6c757d;
            border-color: #6c757d;
        }
        
        .btn-outline-secondary:hover {
            background-color: #6c757d;
            border-color: #6c757d;
            color: white;
        }
        
        .alert {
            border-radius: 6px;
            border: 1px solid transparent;
            padding: 1rem;
            margin-bottom: 1rem;
        }
        
        .alert-success {
            background-color: rgba(40, 167, 69, 0.1);
            border-color: rgba(40, 167, 69, 0.2);
            color: #155724;
        }
        
        .alert-info {
            background-color: rgba(23, 162, 184, 0.1);
            border-color: rgba(23, 162, 184, 0.2);
            color: #0c5460;
        }
        
        .alert-warning {
            background-color: rgba(255, 193, 7, 0.1);
            border-color: rgba(255, 193, 7, 0.2);
            color: #856404;
        }
        
        .alert-danger {
            background-color: rgba(220, 53, 69, 0.1);
            border-color: rgba(220, 53, 69, 0.2);
            color: #721c24;
        }
        
        hr {
            border: 0;
            border-top: 1px solid var(--border-color);
            margin: 1.5rem 0;
        }
        
        .text-muted {
            color: var(--text-muted) !important;
        }
        
        .text-success {
            color: var(--success-color) !important;
        }
        
        .text-warning {
            color: var(--warning-color) !important;
        }
        
        .text-danger {
            color: var(--danger-color) !important;
        }
        
        .text-primary {
            color: var(--primary-color) !important;
        }
        
        
        .tetromino-info {
            display: flex;
            flex-wrap: wrap;
            gap: 1rem;
            margin: 1.5rem 0;
        }
        
        .tetromino-item {
            display: flex;
            flex-direction: column;
            align-items: center;
            width: 80px;
        }
        
        .tetromino-preview {
            width: 60px;
            height: 60px;
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            grid-template-rows: repeat(4, 1fr);
            gap: 1px;
            margin-bottom: 0.5rem;
            background-color: var(--block-empty);
            border: 1px solid var(--border-color);
            border-radius: 4px;
        }
        
        .preview-cell {
            background-color: transparent;
        }
        
        .preview-cell.filled {
            border: none;
        }
        
        .tetromino-name {
            font-size: 0.9rem;
            font-weight: 500;
            color: var(--text-color);
        }