:root {
            --primary-blue: #0b2545;
            --accent-blue: #134074;
            --light-blue: #8da9c4;
            --dark-charcoal: #1d2d44;
            --pure-white: #ffffff;
            --border-color: #e2e8f0;
            --text-main: #334155;
            --alert-red: #d9383a;
        }

        /* ========== 全局基础重置（所有页面通用） ========== */
        * {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }
        body {
            font-family: "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
            color: var(--text-main);
            background-color: var(--pure-white);
            line-height: 1.6;
            font-size: 16px;
            -webkit-font-smoothing: antialiased;
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
        }
        a {
            text-decoration: none;
            color: inherit;
            transition: all 0.3s ease;
        }

        /* ========== 全局容器（页面版心通用） ========== */
        .container {
            width: 100%;
            max-width: 1440px;
            margin: 0 auto;
            padding: 0 40px;
        }

        /* ========== 顶部信息条 top-bar 样式 ========== */
        .top-bar {
            background-color: var(--primary-blue);
            color: var(--pure-white);
            font-size: 14px;
            padding: 12px 0;
            border-bottom: 1px solid rgba(255, 255, 255, 0.1);
        }
        .top-bar-flex {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        /* ========== Header 导航 PC端基础样式 ========== */
        header {
            background: var(--pure-white);
            border-bottom: 1px solid var(--border-color);
            position: sticky;
            top: 0;
            z-index: 1000;
            box-shadow: 0 4px 20px rgba(0, 0, 0, 0.04);
        }
        .header-flex {
            display: flex;
            justify-content: space-between;
            align-items: center;
            height: 80px;
            max-width: 100%;
            padding: 0 12%;
            margin: 0 auto;
            background: #fff;
        }
        .logo-area img {
            height: 55px;
            object-fit: contain;
        }
        nav ul {
            list-style: none;
            display: flex;
            gap: 20px;
        }
        nav ul li a {
            font-size: 16px;
            font-weight: 600;
            color: var(--dark-charcoal);
            padding: 8px 4px;
            letter-spacing: 0.5px;
        }
        nav ul li a:hover,
        nav ul li a.active {
            color: #3399ff;
            background-color: #e6f5ff;
            border-bottom: 6px solid #3399ff;
        }

        /* ========== 汉堡菜单基础样式 ========== */
        .menu-toggle {
            display: none;
            font-size: 28px;
            cursor: pointer;
            color: var(--dark-charcoal);
            padding: 8px;
            flex-shrink: 0;
        }

        /* ========== 移动端768px适配：导航折叠、Logo左汉堡右 ========== */
        @media(max-width: 768px) {
            .container {
                padding: 0 20px;
            }
            .header-flex {
                position: relative;
                flex-wrap: wrap;
                flex-direction: row !important;
                justify-content: space-between;
                align-items: center;
            }
            .menu-toggle {
                display: block;
                order: 2;
            }
            .logo-area {
                order: 1;
            }
            header nav {
                width: 100%;
                position: absolute;
                left: 0;
                top: 100%;
                background: #fff;
                box-shadow: 0 8px 15px rgba(0, 0, 0, 0.08);
                max-height: 0;
                overflow: hidden;
                transition: max-height 0.35s ease;
                order: 3;
            }
            header nav.open {
                max-height: 600px;
            }
            nav ul {
                flex-direction: column;
                padding: 15px 20px;
                gap: 8px !important;
            }
            nav ul li a {
                display: block;
                padding: 10px 0;
                text-align: center;
            }
            .top-bar-flex {
                flex-direction: column;
                text-align: center;
                gap: 15px;
            }
        }
        footer {
            background-color: #2c2f38;
            color: #e2e8f0;
            padding: 50px 0 30px;
        }
        .footer-row {
            display: grid;
            grid-template-columns: 1fr 1fr 1fr 1fr 1fr;
            gap: 30px;
            margin-bottom: 35px;
        }
        .footer-contact-item {
            display: flex;
            align-items: flex-start;
            gap: 14px;
            margin-bottom: 22px;
        }
        .footer-contact-icon {
            width: 50px;
            height: 50px;
            border-radius: 50%;
            background: #444750;
            display: flex;
            align-items: center;
            justify-content: center;
            flex-shrink: 0;
            font-size: 24px;
        }
        .footer-col h5 {
            font-size: 22px;
            margin-bottom: 20px;
            font-weight: 600;
            color: #fff;
        }
        .footer-col ul {
            list-style: none;
        }
        .footer-col ul li {
            margin-bottom: 10px;
            font-size: 16px;
        }
        .footer-col ul li a:hover {
            color: #8da9c4;
        }
        .footer-bottom-text {
            text-align: center;
            padding-top: 25px;
            border-top: 1px solid #444750;
            font-size: 17px;
            color: #b0b8c4;
        }
        .footer-contact-text a {
            font-size: 20px;
            font-weight: 500;
            color: #fff;
        }
        @media(max-width: 1200px) {
            .footer-row {
                grid-template-columns: repeat(3, 1fr);
                gap: 25px;
            }
        }
        @media(max-width: 768px) {
            .footer-row {
                grid-template-columns: 1fr;
            }
        }

        /* ========================================================================
           XNAIR 产品页面专属样式（.xnair- 命名空间，防止与头部底部冲突）
           ======================================================================== */

        /* ---- 面包屑导航 ---- */
        .xnair-breadcrumb-wrap {
            background-color: #f8fafc;
            border-bottom: 1px solid var(--border-color);
            padding: 14px 0;
            font-size: 14px;
            color: #64748b;
        }
        .xnair-breadcrumb-wrap .container {
            display: flex;
            align-items: center;
            flex-wrap: wrap;
            gap: 6px;
        }
        .xnair-breadcrumb-wrap ol {
            list-style: none;
            display: flex;
            flex-wrap: wrap;
            align-items: center;
            gap: 6px;
            margin: 0;
            padding: 0;
        }
        .xnair-breadcrumb-wrap ol li {
            display: inline-flex;
            align-items: center;
            gap: 6px;
        }
        .xnair-breadcrumb-wrap ol li a {
            color: #64748b;
            font-weight: 500;
            transition: color 0.25s;
        }
        .xnair-breadcrumb-wrap ol li a:hover {
            color: var(--accent-blue);
        }
        .xnair-breadcrumb-sep {
            color: #cbd5e1;
            user-select: none;
            font-size: 12px;
        }
        .xnair-breadcrumb-current {
            color: var(--dark-charcoal);
            font-weight: 600;
        }

        /* ---- 主内容两栏布局（桌面端：TOC侧边 + 内容区） ---- */
        .xnair-page-layout {
            display: flex;
            gap: 40px;
            align-items: flex-start;
            padding-top: 32px;
            padding-bottom: 48px;
        }
        .xnair-page-layout .container {
            display: flex;
            gap: 40px;
            align-items: flex-start;
            width: 100%;
            padding: 0 40px;
        }

        /* ---- 侧边 TOC 悬浮目录（垂直列表，禁止左右排列） ---- */
        .xnair-toc-sidebar {
            width: 240px;
            flex-shrink: 0;
            position: sticky;
            top: 100px;
            /* header高度80px + 间距 */;
            background: #f9fafb;
            border: 1px solid var(--border-color);
            border-radius: 8px;
            padding: 20px 18px;
            max-height: calc(100vh - 130px);
            overflow-y: auto;
            z-index: 50;
        }
        .xnair-toc-sidebar h4 {
            font-size: 15px;
            font-weight: 700;
            color: var(--dark-charcoal);
            margin-bottom: 14px;
            letter-spacing: 0.3px;
            text-transform: uppercase;
            border-bottom: 2px solid var(--accent-blue);
            padding-bottom: 8px;
        }
        .xnair-toc-list {
            list-style: none;
            display: flex;
            flex-direction: column;
            /* 强制上下排列 */;
            gap: 6px;
            margin: 0;
            padding: 0;
        }
        .xnair-toc-list li a {
            display: block;
            padding: 7px 10px;
            font-size: 14px;
            color: #475569;
            border-radius: 4px;
            transition: all 0.2s;
            font-weight: 500;
            border-left: 3px solid transparent;
        }
        .xnair-toc-list li a:hover {
            background: #e8f0fe;
            color: var(--accent-blue);
            border-left-color: var(--accent-blue);
        }

        /* ---- 移动端 TOC 折叠（使用 details 元素，零JS） ---- */
        .xnair-toc-mobile {
            display: none;
            margin-bottom: 20px;
            border: 1px solid var(--border-color);
            border-radius: 8px;
            background: #f9fafb;
            overflow: hidden;
        }
        .xnair-toc-mobile summary {
            padding: 14px 18px;
            font-weight: 700;
            font-size: 15px;
            cursor: pointer;
            color: var(--dark-charcoal);
            background: #f1f5f9;
            letter-spacing: 0.3px;
            text-transform: uppercase;
            list-style: none;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        .xnair-toc-mobile summary::-webkit-details-marker {
            display: none;
        }
        .xnair-toc-mobile summary::after {
            content: '▾';
            font-size: 14px;
            transition: transform 0.25s;
        }
        .xnair-toc-mobile[open] summary::after {
            transform: rotate(180deg);
        }
        .xnair-toc-mobile .xnair-toc-list {
            padding: 10px 18px 16px;
        }

        /* ---- 主内容区 ---- */
        .xnair-main-content {
            flex: 1;
            min-width: 0;
        }

        /* ---- Hero 区域 ---- */
        .xnair-hero-wrap {
            display: flex;
            gap: 32px;
            align-items: flex-start;
            margin-bottom: 36px;
            flex-wrap: wrap;
        }
        .xnair-hero-text {
            flex: 1;
            min-width: 280px;
        }
        .xnair-hero-text h1 {
            font-size: 30px;
            font-weight: 800;
            color: var(--dark-charcoal);
            line-height: 1.3;
            margin-bottom: 10px;
            letter-spacing: -0.3px;
        }
        .xnair-hero-subtitle {
            font-size: 16px;
            color: #64748b;
            margin-bottom: 18px;
            line-height: 1.5;
        }
        .xnair-hero-highlights {
            display: flex;
            flex-wrap: wrap;
            gap: 12px;
            margin-bottom: 18px;
        }
        .xnair-hero-highlight-item {
            background: #eef4fb;
            border-left: 4px solid var(--accent-blue);
            padding: 8px 14px;
            font-size: 14px;
            font-weight: 600;
            color: var(--dark-charcoal);
            border-radius: 0 6px 6px 0;
            white-space: nowrap;
        }
        .xnair-hero-image {
            flex: 0 0 420px;
            max-width: 420px;
            border-radius: 10px;
            overflow: hidden;
            background: #f1f5f9;
            border: 1px solid var(--border-color);
        }
        .xnair-hero-image img {
            width: 100%;
            height: auto;
            object-fit: cover;
            display: block;
        }

        /* ---- 产品核心摘要（AI Overview） ---- */
        .xnair-overview-box {
            background: #f8fafc;
            border: 1px solid var(--border-color);
            border-radius: 8px;
            padding: 22px 24px;
            margin-bottom: 36px;
            border-left: 5px solid var(--accent-blue);
        }
        .xnair-overview-box h2 {
            font-size: 20px;
            font-weight: 700;
            color: var(--dark-charcoal);
            margin-bottom: 10px;
        }
        .xnair-overview-box p {
            font-size: 15px;
            color: #475569;
            line-height: 1.7;
            max-width: 780px;
        }

        /* ---- 通用板块标题 ---- */
        .xnair-section-title {
            font-size: 24px;
            font-weight: 700;
            color: var(--dark-charcoal);
            margin-bottom: 16px;
            padding-bottom: 10px;
            border-bottom: 2px solid #e2e8f0;
            letter-spacing: -0.2px;
        }
        .xnair-subsection-title {
            font-size: 19px;
            font-weight: 700;
            color: #1e293b;
            margin-bottom: 10px;
            margin-top: 20px;
        }

        /* ---- 技术规格表格 ---- */
        .xnair-specs-table-wrap {
            overflow-x: auto;
            margin-bottom: 36px;
            border: 1px solid var(--border-color);
            border-radius: 8px;
            background: #fff;
        }
        .xnair-specs-table {
            width: 100%;
            border-collapse: collapse;
            font-size: 15px;
            min-width: 600px;
        }
        .xnair-specs-table thead th {
            background: var(--dark-charcoal);
            color: #fff;
            padding: 14px 16px;
            text-align: left;
            font-weight: 600;
            font-size: 14px;
            letter-spacing: 0.4px;
            text-transform: uppercase;
        }
        .xnair-specs-table tbody td {
            padding: 12px 16px;
            border-bottom: 1px solid #f1f5f9;
            color: #334155;
            vertical-align: top;
        }
        .xnair-specs-table tbody tr:nth-child(even) {
            background: #f9fafb;
        }
        .xnair-specs-table tbody tr:hover {
            background: #eef4fb;
        }
        .xnair-specs-table .xnair-spec-param {
            font-weight: 700;
            color: var(--dark-charcoal);
            white-space: nowrap;
            width: 30%;
        }

        /* ---- 图片板块通用 ---- */
        .xnair-image-block {
            display: flex;
            gap: 28px;
            align-items: flex-start;
            margin-bottom: 32px;
            flex-wrap: wrap;
            background: #fff;
            border: 1px solid var(--border-color);
            border-radius: 10px;
            padding: 20px;
        }
        .xnair-image-block .xnair-image-figure {
            flex: 0 0 320px;
            max-width: 320px;
            border-radius: 8px;
            overflow: hidden;
            background: #f1f5f9;
            border: 1px solid #e8ecf1;
        }
        .xnair-image-block .xnair-image-figure img {
            width: 100%;
            height: auto;
            display: block;
            object-fit: cover;
        }
        .xnair-image-block .xnair-image-caption {
            flex: 1;
            min-width: 250px;
        }
        .xnair-image-block .xnair-image-caption h4 {
            font-size: 17px;
            font-weight: 700;
            color: var(--dark-charcoal);
            margin-bottom: 8px;
        }
        .xnair-image-block .xnair-image-caption p {
            font-size: 14px;
            color: #475569;
            line-height: 1.7;
        }

        /* ---- 工程细节列表 ---- */
        .xnair-engineering-list {
            list-style: none;
            padding: 0;
            margin-bottom: 28px;
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 12px;
        }
        .xnair-engineering-list li {
            background: #f8fafc;
            padding: 13px 16px;
            border-radius: 6px;
            border-left: 4px solid var(--accent-blue);
            font-size: 14px;
            color: #334155;
            line-height: 1.5;
            display: flex;
            align-items: flex-start;
            gap: 10px;
        }
        .xnair-engineering-list li::before {
            content: '✓';
            color: #16a34a;
            font-weight: 700;
            flex-shrink: 0;
            font-size: 16px;
        }

        /* ---- 全球适应性卡片 ---- */
        .xnair-region-cards {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 20px;
            margin-bottom: 32px;
        }
        .xnair-region-card {
            background: #fff;
            border: 1px solid var(--border-color);
            border-radius: 8px;
            padding: 20px;
            transition: box-shadow 0.25s;
        }
        .xnair-region-card:hover {
            box-shadow: 0 6px 22px rgba(0, 0, 0, 0.07);
        }
        .xnair-region-card h3 {
            font-size: 17px;
            font-weight: 700;
            color: var(--dark-charcoal);
            margin-bottom: 8px;
        }
        .xnair-region-card p {
            font-size: 14px;
            color: #475569;
            line-height: 1.65;
        }

        /* ---- FAQ 板块 ---- */
        .xnair-faq-wrap {
            margin-bottom: 32px;
        }
        .xnair-faq-item {
            border: 1px solid var(--border-color);
            border-radius: 8px;
            margin-bottom: 10px;
            overflow: hidden;
            background: #fff;
        }
        .xnair-faq-item summary {
            padding: 16px 20px;
            font-weight: 700;
            font-size: 15px;
            cursor: pointer;
            color: var(--dark-charcoal);
            background: #f9fafb;
            list-style: none;
            display: flex;
            justify-content: space-between;
            align-items: center;
            transition: background 0.2s;
        }
        .xnair-faq-item summary::-webkit-details-marker {
            display: none;
        }
        .xnair-faq-item summary::after {
            content: '+';
            font-size: 20px;
            font-weight: 700;
            color: #64748b;
            transition: transform 0.25s;
        }
        .xnair-faq-item[open] summary::after {
            content: '−';
            transform: rotate(0);
        }
        .xnair-faq-item[open] summary {
            background: #eef4fb;
            color: var(--accent-blue);
        }
        .xnair-faq-answer {
            padding: 16px 20px;
            font-size: 14px;
            color: #475569;
            line-height: 1.7;
            background: #fff;
        }

        /* ---- 品质与认证模块 ---- */
        .xnair-quality-wrap {
            background: #f8fafc;
            border: 1px solid var(--border-color);
            border-radius: 8px;
            padding: 24px;
            margin-bottom: 32px;
            border-left: 5px solid #16a34a;
        }
        .xnair-quality-wrap h2 {
            font-size: 20px;
            font-weight: 700;
            color: var(--dark-charcoal);
            margin-bottom: 12px;
        }
        .xnair-quality-wrap p {
            font-size: 14px;
            color: #475569;
            line-height: 1.7;
            margin-bottom: 10px;
        }
        .xnair-quality-wrap ul {
            list-style: disc;
            padding-left: 20px;
            margin-top: 6px;
        }
        .xnair-quality-wrap ul li {
            font-size: 14px;
            color: #475569;
            margin-bottom: 6px;
            line-height: 1.6;
        }

        /* ---- 相关产品推荐 ---- */
        .xnair-related-products {
            margin-bottom: 32px;
        }
        .xnair-related-grid {
            display: grid;
            grid-template-columns: 1fr 1fr 1fr;
            gap: 16px;
        }
        .xnair-related-card {
            border: 1px solid var(--border-color);
            border-radius: 8px;
            padding: 16px;
            text-align: center;
            background: #fff;
            transition: box-shadow 0.25s;
        }
        .xnair-related-card:hover {
            box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
        }
        .xnair-related-card img {
            width: 100%;
            height: 160px;
            object-fit: cover;
            border-radius: 6px;
            margin-bottom: 10px;
            background: #f1f5f9;
        }
        .xnair-related-card a {
            font-weight: 700;
            font-size: 14px;
            color: var(--dark-charcoal);
            display: inline-block;
            line-height: 1.4;
        }
        .xnair-related-card a:hover {
            color: var(--accent-blue);
        }

        /* ---- 上下篇导航 ---- */
        .xnair-pagination-nav {
            display: flex;
            justify-content: space-between;
            gap: 16px;
            padding: 20px 0;
            border-top: 2px solid #e2e8f0;
            margin-top: 10px;
            flex-wrap: wrap;
        }
        .xnair-pagination-nav a {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 12px 20px;
            background: #f8fafc;
            border: 1px solid var(--border-color);
            border-radius: 6px;
            font-weight: 600;
            font-size: 14px;
            color: var(--dark-charcoal);
            transition: all 0.25s;
            max-width: 48%;
        }
        .xnair-pagination-nav a:hover {
            background: #eef4fb;
            border-color: var(--accent-blue);
            color: var(--accent-blue);
        }
        .xnair-pagination-nav .xnair-prev::before {
            content: '←';
            font-size: 16px;
        }
        .xnair-pagination-nav .xnair-next::after {
            content: '→';
            font-size: 16px;
        }

        /* ---- CTA 询盘按钮 ---- */
        .xnair-cta-btn {
            display: inline-block;
            background: var(--accent-blue);
            color: #fff;
            padding: 12px 28px;
            border-radius: 6px;
            font-weight: 700;
            font-size: 15px;
            letter-spacing: 0.3px;
            transition: all 0.3s;
            text-align: center;
            border: none;
            cursor: pointer;
        }
        .xnair-cta-btn:hover {
            background: #0e3355;
            color: #fff;
            box-shadow: 0 4px 14px rgba(11, 37, 69, 0.25);
        }

        /* ========== 响应式设计 ========== */
        @media(max-width: 1200px) {
            .xnair-hero-image {
                flex: 0 0 340px;
                max-width: 340px;
            }
            .xnair-toc-sidebar {
                width: 200px;
            }
            .xnair-related-grid {
                grid-template-columns: 1fr 1fr;
            }
            .xnair-engineering-list {
                grid-template-columns: 1fr;
            }
            .xnair-region-cards {
                grid-template-columns: 1fr 1fr;
            }
        }

        @media(max-width: 900px) {
            .xnair-page-layout .container {
                flex-direction: column;
                padding: 0 20px;
            }
            .xnair-toc-sidebar {
                display: none;
                /* 桌面TOC隐藏 */;
            }
            .xnair-toc-mobile {
                display: block;
                /* 移动端折叠TOC显示 */;
            }
            .xnair-hero-wrap {
                flex-direction: column;
            }
            .xnair-hero-image {
                flex: 0 0 auto;
                max-width: 100%;
                width: 100%;
            }
            .xnair-hero-text h1 {
                font-size: 24px;
            }
            .xnair-image-block {
                flex-direction: column;
            }
            .xnair-image-block .xnair-image-figure {
                flex: 0 0 auto;
                max-width: 100%;
                width: 100%;
            }
            .xnair-region-cards {
                grid-template-columns: 1fr;
            }
            .xnair-related-grid {
                grid-template-columns: 1fr 1fr;
            }
            .xnair-pagination-nav a {
                max-width: 100%;
                width: 100%;
                justify-content: center;
            }
            .xnair-pagination-nav {
                flex-direction: column;
            }
        }

        @media(max-width: 600px) {
            .xnair-hero-text h1 {
                font-size: 21px;
            }
            .xnair-section-title {
                font-size: 20px;
            }
            .xnair-specs-table {
                font-size: 13px;
                min-width: 480px;
            }
            .xnair-specs-table thead th,
            .xnair-specs-table tbody td {
                padding: 10px 10px;
            }
            .xnair-hero-highlights {
                flex-direction: column;
                gap: 8px;
            }
            .xnair-hero-highlight-item {
                font-size: 13px;
                padding: 6px 10px;
            }
            .xnair-related-grid {
                grid-template-columns: 1fr;
            }
            .xnair-engineering-list {
                grid-template-columns: 1fr;
            }
            .xnair-region-cards {
                grid-template-columns: 1fr;
            }
        }