/* ========== 全站共用变量（所有页面共用配色） ========== */
        :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（用户头部代码） ========== */
        .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（用户头部代码） ========== */
        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（用户头部代码） ========== */
        .menu-toggle {
            display: none;
            font-size: 28px;
            cursor: pointer;
            color: var(--dark-charcoal);
            padding: 8px;
            flex-shrink: 0;
        }

        /* ========== 移动端768px适配（用户头部响应式） ========== */
        @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;
            }
        }

        /* ========== 页脚样式（用户底部代码） ========== */
        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;
        }

        /* 响应式适配页脚部分 */
        @media(max-width: 1200px) {
            .footer-row {
                grid-template-columns: repeat(3, 1fr);
                gap: 25px;
            }
        }
        @media(max-width: 768px) {
            .footer-row {
                grid-template-columns: 1fr;
            }
        }

        /* ================================================================
           ========== 以下为产品内容页专属样式（xnair- 命名空间，不与头部底部冲突）==========
           ================================================================ */

        /* 面包屑导航样式 */
        .xnair-breadcrumb-wrap {
            background: #f8fafc;
            border-bottom: 1px solid var(--border-color);
            padding: 14px 0;
        }
        .xnair-breadcrumb {
            list-style: none;
            display: flex;
            flex-wrap: wrap;
            gap: 6px;
            font-size: 14px;
            color: #64748b;
            align-items: center;
        }
        .xnair-breadcrumb li {
            display: inline-flex;
            align-items: center;
            gap: 6px;
        }
        .xnair-breadcrumb li a {
            color: var(--primary-blue);
            font-weight: 500;
        }
        .xnair-breadcrumb li a:hover {
            color: #3399ff;
            text-decoration: underline;
        }
        .xnair-breadcrumb .xnair-separator {
            color: #94a3b8;
            font-size: 12px;
        }
        .xnair-breadcrumb .xnair-current {
            color: var(--text-main);
            font-weight: 600;
        }

        /* 产品内容主容器：桌面端两栏（TOC侧边栏 + 主内容），移动端单栏 */
        .xnair-content-wrapper {
            display: flex;
            gap: 40px;
            padding: 40px 0 50px;
            align-items: flex-start;
        }

        /* TOC 悬浮目录侧边栏 - 桌面端 sticky */
        .xnair-toc-sidebar {
            width: 240px;
            flex-shrink: 0;
            position: sticky;
            top: 100px;
            /* header高度80px + 间距20px */
            background: #f9fafb;
            border: 1px solid var(--border-color);
            border-radius: 8px;
            padding: 20px 16px;
            max-height: calc(100vh - 140px);
            overflow-y: auto;
        }
        .xnair-toc-sidebar .xnair-toc-title {
            font-size: 14px;
            font-weight: 700;
            color: var(--primary-blue);
            text-transform: uppercase;
            letter-spacing: 1px;
            margin-bottom: 14px;
            padding-bottom: 10px;
            border-bottom: 2px solid #e2e8f0;
        }
        .xnair-toc-sidebar ul {
            list-style: none;
            display: flex;
            flex-direction: column;
            gap: 6px;
        }
        .xnair-toc-sidebar ul li a {
            display: block;
            font-size: 14px;
            color: #475569;
            padding: 7px 10px;
            border-radius: 4px;
            font-weight: 500;
            line-height: 1.4;
            transition: all 0.2s ease;
        }
        .xnair-toc-sidebar ul li a:hover {
            background: #e6f5ff;
            color: #3399ff;
        }
        .xnair-toc-sidebar ul li a.xnair-toc-active {
            background: #e6f5ff;
            color: #0b2545;
            font-weight: 700;
            border-left: 3px solid #3399ff;
        }

        /* 主内容区域 */
        .xnair-main-content {
            flex: 1;
            min-width: 0;
            /* 防止flex子项溢出 */;
        }

        /* Hero 区域 */
        .xnair-hero-wrap {
            margin-bottom: 32px;
        }
        .xnair-hero-wrap h1 {
            font-size: 32px;
            font-weight: 700;
            color: var(--primary-blue);
            line-height: 1.3;
            margin-bottom: 20px;
            letter-spacing: -0.3px;
        }
        .xnair-hero-img {
            width: 100%;
            aspect-ratio: 16 / 7;
            object-fit: cover;
            border-radius: 8px;
            background: #e2e8f0;
        }

        /* AI Overview 摘要卡片 */
        .xnair-ai-summary {
            background: linear-gradient(135deg, #f0f7ff 0%, #f8fafc 100%);
            border: 1px solid #dbeafe;
            border-left: 5px solid #3399ff;
            border-radius: 6px;
            padding: 20px 24px;
            margin-bottom: 36px;
            font-size: 15px;
            color: #1e3a5f;
            line-height: 1.7;
        }
        .xnair-ai-summary strong {
            color: var(--primary-blue);
        }

        /* H2 / H3 通用标题 */
        .xnair-main-content h2 {
            font-size: 24px;
            font-weight: 700;
            color: var(--primary-blue);
            margin: 40px 0 16px;
            padding-bottom: 10px;
            border-bottom: 2px solid #e2e8f0;
            letter-spacing: -0.2px;
        }
        .xnair-main-content h2:first-of-type {
            margin-top: 0;
        }
        .xnair-main-content h3 {
            font-size: 19px;
            font-weight: 600;
            color: #1d2d44;
            margin: 24px 0 10px;
        }
        .xnair-main-content p {
            margin-bottom: 14px;
            color: #475569;
            line-height: 1.75;
        }

        /* 技术规格表格 */
        .xnair-specs-table-wrap {
            overflow-x: auto;
            margin: 20px 0 28px;
            border-radius: 6px;
            border: 1px solid var(--border-color);
        }
        .xnair-specs-table {
            width: 100%;
            border-collapse: collapse;
            font-size: 14px;
            min-width: 600px;
        }
        .xnair-specs-table thead th {
            background: var(--primary-blue);
            color: #fff;
            padding: 13px 16px;
            text-align: left;
            font-weight: 600;
            font-size: 13px;
            letter-spacing: 0.5px;
            white-space: nowrap;
        }
        .xnair-specs-table tbody td {
            padding: 11px 16px;
            border-bottom: 1px solid #e2e8f0;
            color: #334155;
        }
        .xnair-specs-table tbody tr:nth-child(even) {
            background: #f8fafc;
        }
        .xnair-specs-table tbody tr:hover {
            background: #e6f5ff;
        }
        .xnair-specs-table tbody td:first-child {
            font-weight: 600;
            color: #1d2d44;
            white-space: nowrap;
            width: 35%;
        }

        /* 应用场景卡片（图文并排） */
        .xnair-app-card {
            display: flex;
            gap: 24px;
            align-items: center;
            margin: 20px 0 28px;
            background: #f9fafb;
            border-radius: 8px;
            padding: 20px;
            border: 1px solid #e2e8f0;
        }
        .xnair-app-card .xnair-app-img {
            width: 280px;
            flex-shrink: 0;
            aspect-ratio: 4/3;
            object-fit: cover;
            border-radius: 6px;
            background: #e2e8f0;
        }
        .xnair-app-card .xnair-app-text {
            flex: 1;
        }
        .xnair-app-card .xnair-app-text h4 {
            font-size: 17px;
            font-weight: 700;
            color: var(--primary-blue);
            margin-bottom: 8px;
        }
        .xnair-app-card .xnair-app-text p {
            margin-bottom: 8px;
            font-size: 14px;
        }

        /* 工程细节列表 */
        .xnair-eng-list {
            list-style: none;
            padding: 0;
            margin: 16px 0 24px;
        }
        .xnair-eng-list li {
            position: relative;
            padding-left: 28px;
            margin-bottom: 10px;
            font-size: 15px;
            color: #475569;
            line-height: 1.6;
        }
        .xnair-eng-list li::before {
            content: "▸";
            position: absolute;
            left: 0;
            top: 0;
            color: #3399ff;
            font-weight: 700;
            font-size: 16px;
        }

        /* FAQ 折叠面板（纯CSS实现，零JS依赖） */
        .xnair-faq-item {
            border: 1px solid var(--border-color);
            border-radius: 6px;
            margin-bottom: 10px;
            overflow: hidden;
            background: #fff;
        }
        .xnair-faq-item summary {
            padding: 15px 18px;
            font-weight: 600;
            font-size: 15px;
            color: var(--primary-blue);
            cursor: pointer;
            list-style: none;
            display: flex;
            justify-content: space-between;
            align-items: center;
            background: #f9fafb;
            user-select: none;
        }
        .xnair-faq-item summary::-webkit-details-marker {
            display: none;
        }
        .xnair-faq-item summary::after {
            content: "+";
            font-size: 20px;
            font-weight: 700;
            color: #3399ff;
            transition: transform 0.3s ease;
            flex-shrink: 0;
            margin-left: 12px;
        }
        .xnair-faq-item[open] summary::after {
            content: "−";
            transform: rotate(0deg);
        }
        .xnair-faq-item .xnair-faq-answer {
            padding: 16px 18px;
            font-size: 14px;
            color: #475569;
            line-height: 1.7;
            border-top: 1px solid #e2e8f0;
        }

        /* 品质承诺卡片 */
        .xnair-quality-card {
            background: #f0f7ff;
            border: 1px solid #dbeafe;
            border-radius: 8px;
            padding: 24px;
            margin: 24px 0;
        }
        .xnair-quality-card h3 {
            margin-top: 0;
            color: var(--primary-blue);
        }
        .xnair-quality-card ul {
            list-style: disc;
            padding-left: 20px;
            margin: 10px 0;
        }
        .xnair-quality-card ul li {
            margin-bottom: 6px;
            font-size: 14px;
            color: #475569;
        }

        /* 相关产品卡片网格 */
        .xnair-related-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
            gap: 16px;
            margin: 16px 0 28px;
        }
        .xnair-related-card {
            border: 1px solid var(--border-color);
            border-radius: 6px;
            padding: 16px;
            text-align: center;
            transition: box-shadow 0.3s ease;
            background: #fff;
        }
        .xnair-related-card:hover {
            box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
            border-color: #3399ff;
        }
        .xnair-related-card a {
            font-weight: 600;
            color: var(--primary-blue);
            font-size: 14px;
        }
        .xnair-related-card a:hover {
            color: #3399ff;
        }

        /* 上/下篇导航 */
        .xnair-pagination-nav {
            display: flex;
            justify-content: space-between;
            align-items: center;
            gap: 20px;
            padding: 20px 0;
            border-top: 2px solid #e2e8f0;
            border-bottom: 2px solid #e2e8f0;
            margin: 30px 0;
            flex-wrap: wrap;
        }
        .xnair-pagination-nav a {
            font-weight: 600;
            color: var(--primary-blue);
            font-size: 15px;
            padding: 8px 14px;
            border-radius: 4px;
            border: 1px solid #e2e8f0;
            transition: all 0.3s ease;
            max-width: 48%;
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
        }
        .xnair-pagination-nav a:hover {
            background: #e6f5ff;
            border-color: #3399ff;
            color: #3399ff;
        }
        .xnair-pagination-nav .xnair-prev::before {
            content: "← ";
        }
        .xnair-pagination-nav .xnair-next::after {
            content: " →";
        }

        /* ========== 响应式：1024px以下TOC从侧边栏变为顶部折叠模块 ========== */
        @media(max-width: 1024px) {
            .xnair-content-wrapper {
                flex-direction: column;
                gap: 20px;
            }
            .xnair-toc-sidebar {
                width: 100%;
                position: static;
                max-height: none;
                overflow-y: visible;
                border-radius: 6px;
                padding: 14px 16px;
            }
            .xnair-toc-sidebar .xnair-toc-title {
                cursor: pointer;
                display: flex;
                justify-content: space-between;
                align-items: center;
                margin-bottom: 0;
                border-bottom: none;
                padding-bottom: 0;
            }
            .xnair-toc-sidebar .xnair-toc-title::after {
                content: "▾";
                font-size: 16px;
                transition: transform 0.3s ease;
            }
            .xnair-toc-sidebar.xnair-toc-expanded .xnair-toc-title::after {
                transform: rotate(180deg);
            }
            .xnair-toc-sidebar ul {
                max-height: 0;
                overflow: hidden;
                transition: max-height 0.4s ease;
                margin-top: 0;
            }
            .xnair-toc-sidebar.xnair-toc-expanded ul {
                max-height: 600px;
                margin-top: 12px;
            }
            /* 应用卡片在小屏堆叠 */
            .xnair-app-card {
                flex-direction: column;
            }
            .xnair-app-card .xnair-app-img {
                width: 100%;
                aspect-ratio: 16/9;
            }
        }

        /* ========== 响应式：768px以下进一步微调 ========== */
        @media(max-width: 768px) {
            .xnair-hero-wrap h1 {
                font-size: 24px;
            }
            .xnair-main-content h2 {
                font-size: 20px;
            }
            .xnair-main-content h3 {
                font-size: 17px;
            }
            .xnair-specs-table {
                font-size: 12px;
                min-width: 480px;
            }
            .xnair-specs-table thead th,
            .xnair-specs-table tbody td {
                padding: 8px 10px;
            }
            .xnair-pagination-nav {
                flex-direction: column;
                gap: 10px;
            }
            .xnair-pagination-nav a {
                max-width: 100%;
                width: 100%;
                text-align: center;
            }
            .xnair-related-grid {
                grid-template-columns: repeat(2, 1fr);
                gap: 10px;
            }
            .xnair-ai-summary {
                font-size: 14px;
                padding: 16px;
            }
            .xnair-quality-card {
                padding: 16px;
            }
        }
        @media(max-width: 480px) {
            .xnair-related-grid {
                grid-template-columns: 1fr;
            }
            .xnair-hero-wrap h1 {
                font-size: 20px;
            }
            .xnair-hero-img {
                aspect-ratio: 16/10;
            }
        }