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

        body {
            font-family: 'SimSun', '宋体', serif;
            background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
            min-height: 100vh;
            display: flex;
            flex-direction: column;
            align-items: center;
            padding: 20px;
        }

        .header {
            text-align: center;
            margin-bottom: 20px;
            width: 100%;
        }

        .logo-container {
            display: flex;
            align-items: center;
            justify-content: center;
            margin-bottom: 10px;
        }

        .logo {
            width: 50px;
            height: 50px;
            background: linear-gradient(135deg, #1976d2 0%, #1565c0 100%);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-right: 15px;
            color: white;
            font-weight: bold;
            font-size: 24px;
        }

        .institute-name {
            font-size: 28px;
            font-weight: bold;
            color: #2c3e50;
        }

        .container {
            background: white;
            border-radius: 20px;
            box-shadow: 0 20px 40px rgba(0,0,0,0.1);
            padding: 30px;
            max-width: 1200px;
            width: 100%;
            flex: 1;
        }

        h1 {
            text-align: center;
            color: #2c3e50;
            margin-bottom: 30px;
            font-size: 32px;
            font-weight: 600;
        }

        .main-content {
            display: flex;
            gap: 30px;
            align-items: flex-start;
        }

        .canvas-container {
            flex: 2;
            position: relative;
            background: #fafbfc;
            border-radius: 15px;
            padding: 20px;
            border: 2px solid #e1e8ed;
        }

        #geometryCanvas {
            border: 1px solid #ddd;
            border-radius: 10px;
            background: white;
            display: block;
            margin: 0 auto;
        }

        .controls {
            flex: 1;
            background: #f8f9fa;
            border-radius: 15px;
            padding: 25px;
            border: 2px solid #e9ecef;
        }

        .control-group {
            margin-bottom: 25px;
        }

        .control-group h3 {
            color: #495057;
            margin-bottom: 15px;
            font-size: 18px;
            font-weight: 600;
        }

        .btn {
            background: linear-gradient(135deg, #1976d2 0%, #1565c0 100%);
            color: white;
            border: none;
            padding: 12px 24px;
            border-radius: 25px;
            cursor: pointer;
            font-size: 16px;
            font-weight: 500;
            transition: all 0.3s ease;
            width: 100%;
            margin-bottom: 10px;
        }

        .btn:hover {
            transform: translateY(-2px);
            box-shadow: 0 8px 20px rgba(25, 118, 210, 0.4);
        }

        .btn:active {
            transform: translateY(0);
        }

        .btn.reset {
            background: linear-gradient(135deg, #f57c00 0%, #ef6c00 100%);
        }

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

        .slider-container label {
            display: block;
            margin-bottom: 8px;
            color: #495057;
            font-weight: 500;
            font-size: 16px;
        }

        .slider {
            width: 100%;
            height: 6px;
            border-radius: 3px;
            background: #ddd;
            outline: none;
            -webkit-appearance: none;
        }

        .slider::-webkit-slider-thumb {
            -webkit-appearance: none;
            appearance: none;
            width: 20px;
            height: 20px;
            border-radius: 50%;
            background: #1976d2;
            cursor: pointer;
            box-shadow: 0 2px 6px rgba(0,0,0,0.2);
        }

        .info-panel {
            background: #e8f5e8;
            border-radius: 10px;
            padding: 20px;
            margin-top: 20px;
            border-left: 4px solid #4caf50;
        }

        .info-panel h4 {
            color: #2e7d32;
            margin-bottom: 10px;
            font-size: 18px;
        }

        .formula {
            background: white;
            padding: 15px;
            border-radius: 8px;
            margin: 10px 0;
            border: 1px solid #c8e6c9;
            font-family: 'SimSun', '宋体', serif;
            font-size: 16px;
            color: #1b5e20;
        }

        .coordinates {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 10px;
            margin-top: 15px;
        }

        .coord-item {
            background: white;
            padding: 10px;
            border-radius: 6px;
            border: 1px solid #e0e0e0;
            text-align: center;
            font-size: 16px;
        }

        .coord-label {
            font-weight: bold;
            color: #424242;
        }

        .coord-value {
            color: #2e7d32;
            font-family: 'SimSun', '宋体', serif;
        }

        .progress-bar {
            width: 100%;
            height: 8px;
            background: #e0e0e0;
            border-radius: 4px;
            overflow: hidden;
            margin: 15px 0;
        }

        .progress-fill {
            height: 100%;
            background: linear-gradient(90deg, #4caf50, #1976d2);
            width: 0%;
            transition: width 0.3s ease;
        }

        .min-value-highlight {
            background: #fff3cd;
            border: 2px solid #ffc107;
            border-radius: 8px;
            padding: 10px;
            margin: 10px 0;
            text-align: center;
            font-weight: bold;
            color: #856404;
            font-size: 18px;
        }

        .legend {
            background: #f0f8ff;
            border-radius: 8px;
            padding: 15px;
            margin: 10px 0;
            border: 1px solid #b3d9ff;
        }

        .legend-item {
            display: flex;
            align-items: center;
            margin-bottom: 8px;
            font-size: 16px;
        }

        .legend-color {
            width: 20px;
            height: 3px;
            margin-right: 8px;
            border-radius: 2px;
        }

        .footer {
            text-align: center;
            margin-top: 20px;
            padding: 15px;
            color: #666;
            font-size: 16px;
            width: 100%;
        }

        @media (max-width: 768px) {
            .main-content {
                flex-direction: column;
            }
            
            .canvas-container {
                order: 2;
            }
            
            .controls {
                order: 1;
            }
        }