:root {
            --primary-color: #2c3e50;
            --secondary-color: #4fc3f7;
            --accent-color: #2196f3;
            --success-color: #4caf50;
            --danger-color: #f44336;
            --light-color: #f8f9fa;
            --dark-color: #333;
            --border-color: #ddd;
            --shadow: 0 4px 12px rgba(0,0,0,0.08);
            --radius: 8px;
        }
        
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Microsoft YaHei', sans-serif;
        }
        
        body {
            background-color: #f5f7fa;
            color: var(--dark-color);
            line-height: 1.6;
            font-size: 16px;
        }
        
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 16px;
        }
        
        /* 头部样式 */
        header {
            background: linear-gradient(135deg, var(--primary-color) 0%, #3a506b 100%);
            color: white;
            padding: 24px 0;
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
        }
        
        .header-content {
            display: flex;
            flex-direction: column;
            align-items: center;
            text-align: center;
        }
        
        .logo {
            display: flex;
            align-items: center;
            gap: 12px;
            margin-bottom: 12px;
        }
        
        .logo-icon {
            width: 48px;
            height: 48px;
            background-color: var(--secondary-color);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: bold;
            font-size: 24px;
        }
        
        .logo-text h1 {
            font-size: 24px;
            margin-bottom: 4px;
        }
        
        .logo-text p {
            color: #e0e0e0;
            font-size: 14px;
        }
        
        /* 主要内容区域 */
        .main-content {
            display: grid;
            grid-template-columns: 1fr;
            gap: 24px;
            margin: 24px 0;
        }
        
        @media (min-width: 992px) {
            .main-content {
                grid-template-columns: 1fr 1fr;
            }
        }
        
        /* 卡片通用样式 */
        .card {
            background: white;
            border-radius: var(--radius);
            box-shadow: var(--shadow);
            padding: 24px;
            margin-bottom: 24px;
        }
        
        .card-title {
            color: var(--primary-color);
            margin-bottom: 20px;
            padding-bottom: 12px;
            border-bottom: 2px solid var(--secondary-color);
            font-size: 20px;
            display: flex;
            align-items: center;
            gap: 8px;
        }
        
        /* 输入区域 */
        .input-group {
            margin-bottom: 20px;
        }
        
        .input-group label {
            display: block;
            margin-bottom: 8px;
            font-weight: 600;
            color: #444;
        }
        
        .input-group input, .input-group select {
            width: 100%;
            padding: 12px 16px;
            border: 1px solid var(--border-color);
            border-radius: var(--radius);
            font-size: 16px;
            transition: all 0.2s;
        }
        
        .input-group input:focus, .input-group select:focus {
            border-color: var(--secondary-color);
            box-shadow: 0 0 0 3px rgba(79, 195, 247, 0.2);
            outline: none;
        }
        
        /* 纳税期数选择 */
        .period-selector {
            display: flex;
            flex-wrap: wrap;
            gap: 8px;
            margin-top: 8px;
        }
        
        .period-option {
            flex: 1;
            min-width: 60px;
        }
        
        .period-option input[type="radio"] {
            display: none;
        }
        
        .period-option label {
            display: block;
            padding: 12px;
            text-align: center;
            background: var(--light-color);
            border: 1px solid var(--border-color);
            border-radius: var(--radius);
            cursor: pointer;
            transition: all 0.2s;
        }
        
        .period-option input[type="radio"]:checked + label {
            background-color: var(--secondary-color);
            color: white;
            border-color: var(--secondary-color);
        }
        
        /* 五险一金输入 */
        .insurance-options {
            display: flex;
            gap: 12px;
        }
        
        .insurance-option {
            flex: 1;
        }
        
        .insurance-option input[type="radio"] {
            display: none;
        }
        
        .insurance-option label {
            display: block;
            padding: 12px;
            text-align: center;
            background: var(--light-color);
            border: 1px solid var(--border-color);
            border-radius: var(--radius);
            cursor: pointer;
            transition: all 0.2s;
        }
        
        .insurance-option input[type="radio"]:checked + label {
            background-color: var(--secondary-color);
            color: white;
            border-color: var(--secondary-color);
        }
        
        /* 按钮样式 */
        .calculate-btn {
            display: block;
            width: 100%;
            padding: 16px;
            background: linear-gradient(to right, var(--secondary-color), var(--accent-color));
            color: white;
            border: none;
            border-radius: var(--radius);
            font-size: 18px;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s;
            margin-top: 20px;
        }
        
        .calculate-btn:hover {
            background: linear-gradient(to right, #29b6f6, #1976d2);
            transform: translateY(-2px);
            box-shadow: 0 6px 12px rgba(33, 150, 243, 0.3);
        }
        
        /* 结果区域 */
        .result-card {
            display: block;
        }
        
        .result-summary {
            display: grid;
            grid-template-columns: 1fr;
            gap: 16px;
            margin-bottom: 24px;
        }
        
        @media (min-width: 576px) {
            .result-summary {
                grid-template-columns: 1fr 1fr;
            }
        }
        
        .result-item {
            padding: 16px;
            border-radius: var(--radius);
            background: var(--light-color);
        }
        
        .result-item.highlight {
            background: linear-gradient(135deg, #e3f2fd, #bbdefb);
            border: 2px solid var(--accent-color);
        }
        
        .result-label {
            font-size: 14px;
            color: #666;
            margin-bottom: 4px;
        }
        
        .result-value {
            font-size: 20px;
            font-weight: 700;
            color: var(--primary-color);
        }
        
        .result-value.tax {
            color: var(--danger-color);
        }
        
        .result-value.income {
            color: var(--success-color);
        }
        
        .result-value.empty {
            color: #999;
            font-weight: normal;
        }
        
        /* 结果详情表格 */
        .result-details {
            width: 100%;
            border-collapse: collapse;
            margin-top: 20px;
        }
        
        .result-details th {
            background-color: var(--primary-color);
            color: white;
            padding: 12px;
            text-align: center;
            font-weight: 600;
        }
        
        .result-details td {
            padding: 12px;
            text-align: center;
            border-bottom: 1px solid var(--border-color);
        }
        
        .result-details tr:nth-child(even) {
            background-color: #f8f9fa;
        }
        
        /* 全宽内容区域 */
        .full-width-section {
            grid-column: 1 / -1;
        }
        
        /* 税率表样式 */
        .tax-table-container {
            overflow-x: auto;
        }
        
        .tax-table {
            width: 100%;
            border-collapse: collapse;
            margin-top: 16px;
            min-width: 500px;
        }
        
        .tax-table th {
            background-color: var(--primary-color);
            color: white;
            padding: 14px;
            text-align: center;
            font-weight: 600;
        }
        
        .tax-table td {
            padding: 12px;
            text-align: center;
            border-bottom: 1px solid var(--border-color);
        }
        
        .tax-table tr:nth-child(even) {
            background-color: #f8f9fa;
        }
        
        /* 信息卡片样式 */
        .info-card {
            background: white;
            border-radius: var(--radius);
            box-shadow: var(--shadow);
            padding: 24px;
            margin-bottom: 24px;
        }
        
        .info-title {
            color: var(--primary-color);
            margin-bottom: 16px;
            padding-bottom: 8px;
            border-bottom: 2px solid var(--secondary-color);
            font-size: 20px;
        }
        
        /* 常见问题样式 */
        .faq-container {
            margin-top: 8px;
        }
        
        details {
            margin-bottom: 12px;
            border: 1px solid var(--border-color);
            border-radius: var(--radius);
            overflow: hidden;
        }
        
        summary {
            padding: 16px;
            background: var(--light-color);
            font-weight: 600;
            cursor: pointer;
            outline: none;
        }
        
        details[open] summary {
            background-color: #e9ecef;
        }
        
        .faq-answer {
            padding: 16px;
            background: white;
        }
        
        /* 新增内容区域 */
        .additional-content {
            display: grid;
            grid-template-columns: 1fr;
            gap: 24px;
            margin-top: 24px;
        }
        
        @media (min-width: 768px) {
            .additional-content {
                grid-template-columns: 1fr 1fr;
            }
        }
        
        /* 页脚样式 */
        footer {
            background: var(--primary-color);
            color: #ddd;
            padding: 32px 0 16px;
            margin-top: 40px;
        }
        
        .footer-content {
            display: grid;
            grid-template-columns: 1fr;
            gap: 24px;
            margin-bottom: 24px;
        }
        
        @media (min-width: 768px) {
            .footer-content {
                grid-template-columns: 1fr 1fr 1fr;
            }
        }
        
        .footer-section h3 {
            color: white;
            margin-bottom: 16px;
            font-size: 18px;
        }
        
        .footer-section ul {
            list-style: none;
        }
        
        .footer-section ul li {
            margin-bottom: 8px;
        }
        
        .footer-section ul li a {
            color: #bbb;
            text-decoration: none;
            transition: color 0.3s;
        }
        
        .footer-section ul li a:hover {
            color: var(--secondary-color);
        }
        
        .copyright {
            text-align: center;
            padding-top: 16px;
            border-top: 1px solid #3a506b;
            color: #aaa;
            font-size: 14px;
        }
        
        /* 打印样式 */
        @media print {
            .calculate-btn, summary {
                display: none;
            }
            
            .card, .info-card {
                box-shadow: none;
                border: 1px solid var(--border-color);
            }
        }