* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: "Microsoft YaHei", sans-serif;
        }
        body {
            background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
            min-height: 100vh;
            padding: 40px 20px;
        }
        /* 容器最大宽度1200px 居中 */
        .container {
            max-width: 1200px;
            margin: 0 auto;
        }
        /* 顶部标题 */
        .page-title {
            text-align: center;
            font-size: 32px;
            font-weight: 700;
            color: #333;
            margin-bottom: 30px;
            letter-spacing: 2px;
        }
        /* 搜索区域 */
        .search-wrap {
            background: #fff;
            border-radius: 8px;
            box-shadow: 0 2px 15px rgba(0,0,0,0.06);
            padding: 15px;
            margin-bottom: 40px;
            display: flex;
            align-items: center;
            gap: 10px;
            max-width: 800px;
            margin-left: auto;
            margin-right: auto;
        }
        .search-select {
            position: relative;
            min-width: 100px;
        }
        .search-select select {
            width: 100%;
            height: 44px;
            padding: 0 15px;
            border: 1px solid #e5e6eb;
            border-radius: 6px;
            outline: none;
            background: #f8f9fa;
            font-size: 16px;
            color: #333;
            cursor: pointer;
            appearance: none;
            background-image: url("data:image/svg+xml;charset=utf-8,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath fill='%23666' d='M10.84 1.84L6 6.69 1.16 1.84A1 1 0 0 0 -0.16 3.16l6 6a1 1 0 0 0 1.32 0l6-6a1 1 0 0 0 -1.32-1.32z'/%3E%3C/svg%3E");
            background-repeat: no-repeat;
            background-position: right 10px center;
        }
        .search-input {
            flex: 1;
            max-width: 560px;
        }
        .search-input input {
            width: 100%;
            height: 44px;
            border: 1px solid #e5e6eb;
            border-radius: 6px;
            outline: none;
            padding: 0 20px;
            font-size: 16px;
            color: #333;
        }
        .search-input input::placeholder {
            color: #999;
        }
        .search-btn button {
            height: 44px;
            padding: 0 25px;
            border: none;
            border-radius: 6px;
            background: #0078d4;
            color: #fff;
            font-size: 16px;
            cursor: pointer;
            transition: all 0.3s;
        }
        .search-btn button:hover {
            background: #0063b1;
        }
        /* 导航分类 阶梯式响应式布局 */
        .nav-categories {
            display: grid;
            grid-template-columns: repeat(3, 1fr); /* 默认3列（大屏电脑） */
            gap: 25px;
            margin-bottom: 40px;
        }
        .nav-category {
            background: #fff;
            border-radius: 8px;
            box-shadow: 0 2px 15px rgba(0,0,0,0.06);
            padding: 20px;
            height: 100%;
        }
        .category-title {
            font-size: 18px;
            font-weight: 600;
            color: #333;
            padding-bottom: 12px;
            margin-bottom: 15px;
            border-bottom: 2px solid #0078d4;
        }
        /* 单行靠左 等高铁框链接 */
        .link-list {
            display: flex;
            flex-direction: column;
            gap: 10px;
        }
        .link-item {
            height: 40px;
            line-height: 40px;
        }
        .link-item a {
            text-decoration: none;
            color: #333;
            font-size: 15px;
            padding: 0 12px;
            border-radius: 4px;
            background: #f8f9fa;
            display: block;
            width: 100%;
            height: 100%;
            text-align: left;
            transition: all 0.2s;
        }
        .link-item a:hover {
            background: #f0f7ff;
            color: #0078d4;
        }
        /* 分割线 */
        .split-line {
            width: 100%;
            height: 1px;
            background: #e5e6eb;
            margin-bottom: 20px;
        }
        /* 底部文字 居中 */
        .footer-text {
            text-align: center;
            font-size: 14px;
            color: #999;
            line-height: 1.6;
        }

        /* 阶梯式响应式：1024px以下显示2列（平板/小屏电脑） */
        @media (max-width: 1024px) {
            .nav-categories {
                grid-template-columns: repeat(2, 1fr);
                gap: 20px;
            }
            .container {
                max-width: 900px;
            }
        }

        /* 768px以下显示1列（手机） */
        @media (max-width: 768px) {
            .page-title {
                font-size: 28px;
                margin-bottom: 20px;
            }
            .search-wrap {
                flex-direction: column;
                gap: 12px;
                max-width: 100%;
            }
            .search-select, .search-input {
                width: 100%;
                max-width: 100%;
            }
            .nav-categories {
                grid-template-columns: 1fr;
                gap: 18px;
            }
            .container {
                max-width: 100%;
            }
        }