    <style>
        * {
            box-sizing: border-box;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
        }
        
        /* 整体布局调整 */
        body {
            margin: 0;
            padding: 0;
            background: #f5f5f5;
            display: flex;
            flex-direction: column;
            min-height: 100vh;
        }
        
        /* Header容器 */
        .header-container {
            width: 100%;
        }
        
        /* 主内容区 */
        .main-content {
            flex: 1;
            width: 100%;
            max-width: 800px;
            margin: 0 auto;
            padding: 20px;
            box-sizing: border-box;
        }
        
        .calculator {
            background: white;
            border-radius: 10px;
            padding: 25px;
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
        }
        
        h1 {
            color: #2c3e50;
            text-align: center;
            margin-bottom: 30px;
        }
        
        .input-group {
            margin-bottom: 20px;
        }
        
        label {
            display: block;
            margin-bottom: 8px;
            font-weight: 600;
            color: #34495e;
        }
        
        input, select {
            width: 100%;
            padding: 12px;
            border: 1px solid #ddd;
            border-radius: 6px;
            font-size: 16px;
        }
        
        .row {
            display: flex;
            gap: 20px;
            margin-bottom: 20px;
        }
        
        .col {
            flex: 1;
        }
        
        button {
            background: #3498db;
            color: white;
            border: none;
            padding: 12px 20px;
            border-radius: 6px;
            font-size: 16px;
            cursor: pointer;
            width: 100%;
            transition: background 0.3s;
        }
        
        button:hover {
            background: #2980b9;
        }
        
        .result {
            margin-top: 30px;
            padding: 20px;
            background: #f8f9fa;
            border-radius: 8px;
            display: none;
        }
        
        .result-item {
            display: flex;
            justify-content: space-between;
            margin-bottom: 10px;
            padding-bottom: 10px;
            border-bottom: 1px solid #eee;
        }
        
        .result-item:last-child {
            border-bottom: none;
            margin-bottom: 0;
            padding-bottom: 0;
        }
        
        .result-label {
            font-weight: 600;
            color: #7f8c8d;
        }
        
        .result-value {
            font-weight: 600;
            color: #2c3e50;
        }
        
        .note {
            margin-top: 20px;
            padding: 15px;
            background: #fff8e1;
            border-left: 4px solid #ffc107;
            font-size: 14px;
            color: #5d4037;
        }
        
        .chart-container {
            height: 300px;
            margin-top: 30px;
        }
        
        /* Footer容器 */
        .footer-container {
            width: 100%;
        }
    </style>