* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            font-family: 'SimSun', '宋体', serif;
            background: #F4F3EC;
            min-height: 100vh;
            display: flex;
            flex-direction: column;
        }

        .header {
            background: #FF5600;
            color: white;
            padding: 25px;
            text-align: center;
            box-shadow: 0 2px 10px rgba(255, 86, 0, 0.3);
        }

        .header h1 {
            font-size: 32px;
            margin-bottom: 10px;
            font-weight: bold;
        }

        .header p {
            font-size: 18px;
            opacity: 0.95;
        }

        .main-container {
            display: flex;
            flex: 1;
            gap: 25px;
            padding: 25px;
            max-width: 1400px;
            margin: 0 auto;
            width: 100%;
        }

        .control-panel {
            width: 350px;
            background: white;
            border-radius: 12px;
            box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
            padding: 25px;
            height: fit-content;
        }

        .canvas-container {
            flex: 1;
            background: white;
            border-radius: 12px;
            box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
            padding: 25px;
            position: relative;
        }

        #geometryCanvas {
            width: 100%;
            height: 650px;
            border: 2px solid #e0e0e0;
            border-radius: 8px;
            background: #fafafa;
            cursor: crosshair;
        }

        .control-group {
            margin-bottom: 25px;
            padding: 20px;
            background: #f8f9fa;
            border-radius: 10px;
            border: 1px solid #e9ecef;
        }

        .control-label {
            font-size: 18px;
            font-weight: bold;
            color: #0C0302;
            margin-bottom: 15px;
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .symmetry-buttons {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 12px;
            margin-bottom: 20px;
        }

        .symmetry-btn {
            padding: 15px 20px;
            border: none;
            border-radius: 8px;
            font-size: 16px;
            font-weight: bold;
            cursor: pointer;
            transition: all 0.3s ease;
            background: #f5f5f5;
            color: #74706E;
            font-family: inherit;
        }

        .symmetry-btn.active {
            background: #FF5600;
            color: white;
            transform: translateY(-2px);
            box-shadow: 0 4px 12px rgba(255, 86, 0, 0.3);
        }

        .symmetry-btn:hover {
            transform: translateY(-1px);
            box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
        }

        .shape-selector {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 10px;
            margin-bottom: 20px;
        }

        .shape-btn {
            padding: 12px;
            border: 2px solid #e0e0e0;
            border-radius: 6px;
            background: white;
            cursor: pointer;
            transition: all 0.3s ease;
            text-align: center;
            font-size: 14px;
            font-family: inherit;
        }

        .shape-btn.active {
            border-color: #FF5600;
            background: #fff5f2;
            color: #FF5600;
        }

        .slider-container {
            margin-bottom: 15px;
        }

        .slider-label {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 8px;
            font-size: 16px;
            color: #0C0302;
        }

        .slider-value {
            background: #FF8941;
            color: white;
            padding: 4px 10px;
            border-radius: 4px;
            font-weight: bold;
            min-width: 60px;
            text-align: center;
        }

        input[type="range"] {
            width: 100%;
            height: 8px;
            border-radius: 4px;
            background: #ddd;
            outline: none;
            -webkit-appearance: none;
            appearance: none;
        }

        input[type="range"]::-webkit-slider-thumb {
            -webkit-appearance: none;
            appearance: none;
            width: 20px;
            height: 20px;
            border-radius: 50%;
            background: #FF5600;
            cursor: pointer;
            box-shadow: 0 2px 6px rgba(255, 86, 0, 0.3);
        }

        input[type="range"]::-moz-range-thumb {
            width: 20px;
            height: 20px;
            border-radius: 50%;
            background: #FF5600;
            cursor: pointer;
            border: none;
            box-shadow: 0 2px 6px rgba(255, 86, 0, 0.3);
        }

        .action-buttons {
            display: flex;
            gap: 12px;
            flex-wrap: wrap;
        }

        .action-btn {
            flex: 1;
            padding: 15px 20px;
            border: none;
            border-radius: 8px;
            font-size: 16px;
            font-weight: bold;
            cursor: pointer;
            transition: all 0.3s ease;
            min-width: 100px;
            font-family: inherit;
        }

        .demo-btn {
            background: #FF5600;
            color: white;
        }

        .demo-btn:hover {
            background: #e64a00;
            transform: translateY(-1px);
        }

        .reset-btn {
            background: #74706E;
            color: white;
        }

        .reset-btn:hover {
            background: #5a5654;
            transform: translateY(-1px);
        }

        .info-panel {
            background: white;
            border-radius: 10px;
            padding: 20px;
            margin-top: 20px;
            border: 1px solid #e9ecef;
        }

        .info-title {
            font-size: 18px;
            font-weight: bold;
            color: #0C0302;
            margin-bottom: 15px;
        }

        .property-display {
            font-size: 16px;
            line-height: 1.6;
            color: #74706E;
        }

        .verification-result {
            margin-top: 15px;
            padding: 12px;
            border-radius: 6px;
            font-weight: bold;
            text-align: center;
        }

        .verification-success {
            background: #d4edda;
            color: #155724;
            border: 1px solid #c3e6cb;
        }

        .verification-error {
            background: #f8d7da;
            color: #721c24;
            border: 1px solid #f5c6cb;
        }

        /* 响应式设计 */
        @media (max-width: 1024px) {
            .main-container {
                flex-direction: column;
                padding: 20px;
                gap: 20px;
            }
            
            .control-panel {
                width: 100%;
            }
            
            #geometryCanvas {
                height: 500px;
            }
        }

        @media (max-width: 768px) {
            .header h1 {
                font-size: 26px;
            }
            
            .header p {
                font-size: 16px;
            }
            
            .main-container {
                padding: 15px;
            }
            
            .symmetry-buttons {
                grid-template-columns: 1fr;
                gap: 10px;
            }
            
            .shape-selector {
                grid-template-columns: repeat(2, 1fr);
            }
            
            #geometryCanvas {
                height: 450px;
            }
        }

        @media (max-width: 480px) {
            .header {
                padding: 20px;
            }
            
            .header h1 {
                font-size: 22px;
            }
            
            .control-panel {
                padding: 20px;
            }
            
            .action-buttons {
                flex-direction: column;
            }
            
            #geometryCanvas {
                height: 400px;
            }
        }