/* --- 基础样式重置 --- */
        :root {
            --primary-color: #0056b3;
            --accent-color: #004494;
            --text-dark: #333333;
            --text-gray: #666666;
            --text-light: #999999;
            --bg-light: #f8f9fa;
            --border-color: #e9ecef;
            --white: #ffffff;
            --font-main: "Helvetica Neue", Helvetica, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
            --transition: all 0.3s ease;
        }
        * { margin: 0; padding: 0; box-sizing: border-box; }
        body { font-family: var(--font-main); color: var(--text-dark); line-height: 1.7; background-color: #fff; font-size: 16px; padding-top: 45px; /* 为顶部条预留空间，防止滚动时内容被遮挡 */ }
        a { text-decoration: none; color: inherit; transition: var(--transition); }
        ul { list-style: none; }
        img { max-width: 100%; height: auto; display: block; }
        .container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
        .section-padding { padding: 80px 0; }
        .text-center { text-align: center; }
        .text-primary { color: var(--primary-color); }
        .btn { display: inline-block; padding: 14px 32px; border-radius: 4px; font-weight: 600; cursor: pointer; transition: var(--transition); text-transform: uppercase; letter-spacing: 1px; font-size: 14px; }
        .btn-primary { background: var(--primary-color); color: #fff; border: 1px solid var(--primary-color); }
        .btn-primary:hover { background: var(--accent-color); border-color: var(--accent-color); }
        .btn-outline { background: transparent; color: #fff; border: 1px solid #fff; }
        .btn-outline:hover { background: #fff; color: var(--primary-color); }

        /* ================= 顶部快捷导航条 (Top Tab Bar) ================= */
        /* 修改逻辑：PC端使用 fixed 定位但预留 body padding，或者使用 relative 占据文档流。
           这里采用 fixed 定位 + body padding 方案，体验更好。
        */
        .top-tab-bar {
            background-color: #f0f4f8;
            border-bottom: 1px solid #e1e8ed;
            font-size: 13px;
            color: var(--text-light);
            height: 45px;
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            z-index: 1001; /* 低于主导航的 z-index，或者主导航滚动后覆盖它 */
            transition: transform 0.3s ease;
        }
        .top-tab-inner { display: flex; justify-content: space-between; align-items: center; height: 100%; }
        .top-tab-links { display: flex; align-items: center; gap: 5px; overflow-x: auto; scrollbar-width: none; }
        .top-tab-links::-webkit-scrollbar { display: none; }
        .top-tab-item { display: flex; align-items: center; gap: 5px; padding: 5px 12px; border-radius: 20px; color: var(--text-light); white-space: nowrap; transition: var(--transition); }
        .top-tab-item:hover { background-color: var(--primary-color); color: var(--white); }
        .tab-icon { font-size: 14px; }
        .top-tab-contact { display: flex; align-items: center; gap: 8px; white-space: nowrap; }
        .contact-phone { color: var(--accent-color); font-weight: bold; font-size: 15px; }
        .contact-phone:hover { text-decoration: underline; }
        .contact-divider { color: #ccc; }

        /* ================= 头部导航 (Header) ================= */
        header {
            background: #fff;
            box-shadow: 0 2px 10px rgba(0,0,0,0.05);
            position: sticky;
            top: 0; /* 粘性定位，滚动时吸附顶部 */
            z-index: 1002; /* 必须高于顶部条 */
            height: 70px;
            display: flex;
            align-items: center;
        }
        .nav-wrapper { display: flex; justify-content: space-between; align-items: center; width: 100%; }
        .logo { font-size: 20px; font-weight: bold; color: var(--primary-color); display: flex; align-items: center; }
        .logo span { color: var(--text-dark); margin-left: 15px; font-size: 14px; }
        .nav-menu { display: flex; gap: 30px; }
        .nav-menu a { font-weight: 500; color: var(--text-dark); font-size: 16px; }
        .nav-menu a:hover, .nav-menu a.active { color: var(--primary-color); }
        .nav-cta { display: flex; gap: 15px; }
        .mobile-menu-btn { display: none; font-size: 28px; color: var(--text-dark); cursor: pointer; }


        /* 首屏Banner */
        .hero {
            background: linear-gradient(135deg, var(--primary-color) 0%, #001f3f 100%);
            color: var(--white);
            padding: 100px 0;
            position: relative;
            overflow: hidden;
        }
        .hero::before {
            content: '';
            position: absolute;
            top: 0; right: 0; bottom: 0; left: 0;
            background: url('https://images.unsplash.com/photo-1486406146926-c627a92ad1ab?ixlib=rb-1.2.1&auto=format&fit=crop&w=1950&q=80') center/cover no-repeat;
            opacity: 0.1;
        }
        .hero-content { position: relative; z-index: 1; max-width: 800px; margin: 0 auto; text-align: center; }
        .hero h1 { font-size: 2.5rem; margin-bottom: 20px; font-family: 'Noto Serif SC', serif; }
        .hero p { font-size: 1.1rem; margin-bottom: 40px; opacity: 0.9; }
        .hero-btns { display: flex; justify-content: center; gap: 20px; }

        /* 业务概述 */
        .overview { padding: 60px 0; background: var(--white); }
        .overview p { font-size: 1.1rem; color: var(--text-light); max-width: 900px; margin: 0 auto; text-align: justify; }

        /* 三大核心品类 */
        .categories { background: var(--bg-light); }
        .section-title { font-size: 2rem; margin-bottom: 15px; font-family: 'Noto Serif SC', serif; color: var(--primary-color); }
        .section-subtitle { color: var(--text-light); margin-bottom: 60px; font-size: 1rem; }
        
        .category-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }
        .category-card {
            background: var(--white);
            padding: 40px 30px;
            border-radius: 8px;
            box-shadow: 0 5px 20px rgba(0,0,0,0.05);
            transition: transform 0.3s, box-shadow 0.3s;
            border-top: 4px solid var(--primary-color);
            height: 100%;
            display: flex;
            flex-direction: column;
        }
        .category-card:hover { transform: translateY(-10px); box-shadow: 0 15px 30px rgba(0,0,0,0.1); }
        .category-card h3 { font-size: 1.5rem; margin-bottom: 20px; color: var(--primary-color); }
        .category-card h4 { font-size: 1.1rem; margin: 15px 0 10px; color: var(--text-dark); }
        .category-card p { font-size: 0.95rem; color: var(--text-light); margin-bottom: 15px; flex-grow: 1; }
        .tag-list { margin-top: auto; }
        .tag { display: inline-block; background: var(--bg-light); padding: 5px 10px; border-radius: 4px; font-size: 0.8rem; margin-right: 5px; margin-bottom: 5px; color: var(--text-dark); }

        /* 流程步骤 */
        .process-steps { display: flex; flex-direction: column; gap: 20px; max-width: 900px; margin: 0 auto; }
        .step-item { display: flex; gap: 20px; background: var(--white); padding: 30px; border-radius: 8px; box-shadow: 0 5px 15px rgba(0,0,0,0.03); align-items: flex-start; }
        .step-num { 
            background: var(--primary-color); color: var(--white); 
            width: 40px; height: 40px; border-radius: 50%; 
            display: flex; align-items: center; justify-content: center; 
            font-weight: 700; flex-shrink: 0;
        }
        .step-content h4 { margin-bottom: 10px; color: var(--primary-color); }
        .step-content p { font-size: 0.95rem; color: var(--text-light); }

        /* 资料清单 */
        .checklist-table { width: 100%; border-collapse: collapse; margin-top: 40px; background: var(--white); box-shadow: 0 5px 15px rgba(0,0,0,0.05); border-radius: 8px; overflow: hidden; }
        .checklist-table th, .checklist-table td { padding: 20px; text-align: left; border-bottom: 1px solid #eee; }
        .checklist-table th { background: var(--primary-color); color: var(--white); font-weight: 500; width: 30%; }
        .checklist-table td { color: var(--text-dark); }
        .checklist-table tr:last-child td { border-bottom: none; }

        /* 估值方案 */
        .valuation-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 40px; }
        .valuation-item h4 { color: var(--primary-color); margin-bottom: 15px; font-size: 1.2rem; border-left: 4px solid var(--accent-color); padding-left: 15px; }
        .valuation-item ul { padding-left: 20px; }
        .valuation-item li { margin-bottom: 10px; color: var(--text-light); position: relative; }
        .valuation-item li::before { content: '•'; color: var(--accent-color); font-weight: bold; position: absolute; left: -10px; }

        /* 服务内容 */
        .service-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; max-width: 900px; margin: 0 auto; }
        .service-item { display: flex; gap: 15px; align-items: flex-start; background: var(--white); padding: 20px; border-radius: 8px; border: 1px solid #eee; }
        .service-item::before { content: '✓'; color: var(--primary-color); font-weight: bold; font-size: 1.2rem; }

        /* 注意事项 */
        .notice-box { background: #fff8e1; border-left: 5px solid var(--accent-color); padding: 20px; margin-bottom: 20px; border-radius: 4px; }
        .notice-box h4 { color: #fbc02d; margin-bottom: 10px; display: flex; align-items: center; gap: 10px; }
        .notice-box p { color: var(--text-dark); font-size: 0.95rem; }

        /* FAQ */
        .faq-item { border-bottom: 1px solid #eee; margin-bottom: 10px; }
        .faq-question { 
            padding: 20px; cursor: pointer; font-weight: 500; 
            display: flex; justify-content: space-between; align-items: center; 
            color: var(--primary-color); font-size: 1.1rem;
        }
        .faq-question::after { content: '+'; font-size: 1.5rem; color: var(--accent-color); }
        .faq-answer { 
            max-height: 0; overflow: hidden; transition: max-height 0.3s ease; 
            padding: 0 20px; color: var(--text-light); background: var(--bg-light);
        }
        .faq-item.active .faq-answer { max-height: 200px; padding: 20px; }
        .faq-item.active .faq-question::after { content: '-'; }

        /* 底部 */
        footer { background: #1a1a1a; color: #ccc; padding: 80px 0 30px; font-size: 0.9rem; }
        .footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 50px; margin-bottom: 50px; }
        .footer-brand h3 { color: var(--white); font-size: 1.5rem; margin-bottom: 20px; font-family: 'Noto Serif SC', serif; }
        .footer-nav h3, .footer-legal h3 { color: var(--white); margin-bottom: 20px; font-size: 1.1rem; }
        .footer-nav ul li, .footer-legal ul li { margin-bottom: 10px; }
        .footer-nav a:hover { color: var(--accent-color); }
        .copyright { text-align: center; border-top: 1px solid #333; padding-top: 30px; font-size: 0.85rem; }

        /* 移动端适配 */
        @media (max-width: 768px) {
            .nav-menu, .nav-cta { display: none; } /* 简化移动端导航 */
           
            .hero h1 { font-size: 1.8rem; }
            .category-grid, .valuation-grid, .service-list, .footer-grid { grid-template-columns: 1fr; }
            .checklist-table, .checklist-table tbody, .checklist-table tr, .checklist-table td, .checklist-table th { display: block; width: 100%; }
            .checklist-table tr { margin-bottom: 15px; border: 1px solid #eee; border-radius: 8px; overflow: hidden; }
            .checklist-table th { width: 100%; background: #f0f0f0; color: #333; border-bottom: 1px solid #ddd; }
            .section-padding { padding: 50px 0; }
             /* 1. 隐藏顶部快捷条，释放空间 */
            .top-tab-bar {     position: inherit; }
            .top-tab-contact{display: none;}
            body { padding-top: 0; } /* 移除 body 的顶部 padding */

            /* 2. 导航栏调整 */
            .mobile-menu-btn { display: block; }
            .nav-menu {
                display: none; /* 默认隐藏 */
                position: absolute;
                top: 70px; /* 导航栏高度 */
                left: 0;
                width: 100%;
                background: #fff;
                flex-direction: column;
                padding: 20px;
                box-shadow: 0 5px 10px rgba(0,0,0,0.1);
                gap: 15px;
                border-bottom: 1px solid var(--border-color);
            }
            .nav-menu.active { display: flex; } /* 激活时显示 */
            .nav-cta { display: none; } /* 隐藏顶部CTA按钮 */

        }