/* ========== 全站共用变量（必须最先引入，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 ========== */
        .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;
            }

            /* 顶部通栏移动端微调 */
            .top-bar-flex {
                flex-direction: column;
                text-align: center;
                gap: 15px;
            }
        }
        /*footer底部样式*/
        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 xnair 产品详情页专属CSS（与头部底部完全隔离） ==========
           ================================================================ */
        /* xnair 面包屑导航 */
        .xnair-breadcrumb-wrap {
            background: #f8fafc;
            border-bottom: 1px solid var(--border-color);
            padding: 14px 0;
        }
        .xnair-breadcrumb {
            display: flex;
            align-items: center;
            flex-wrap: wrap;
            gap: 6px;
            font-size: 14px;
            color: #64748b;
            list-style: none;
        }
        .xnair-breadcrumb li {
            display: inline-flex;
            align-items: center;
            gap: 6px;
        }
        .xnair-breadcrumb li a {
            color: var(--accent-blue);
            font-weight: 500;
        }
        .xnair-breadcrumb li a:hover {
            color: #3399ff;
            text-decoration: underline;
        }
        .xnair-breadcrumb-sep {
            color: #cbd5e1;
            user-select: none;
        }
        .xnair-breadcrumb-current {
            color: var(--text-main);
            font-weight: 600;
        }

        /* xnair 主内容区两栏布局 */
        .xnair-main-wrapper {
            display: flex;
            gap: 40px;
            padding: 40px 0 50px;
            align-items: flex-start;
        }
        .xnair-content-area {
            flex: 1;
            min-width: 0;
        }

        /* xnair TOC 悬浮侧边栏（桌面端sticky） */
        .xnair-toc-sidebar {
            width: 260px;
            flex-shrink: 0;
            position: sticky;
            top: 100px;
            /* header高度80px + 20px间距 */
            background: #f9fafb;
            border: 1px solid var(--border-color);
            border-radius: 8px;
            padding: 20px 18px;
            max-height: calc(100vh - 140px);
            overflow-y: auto;
            z-index: 10;
        }
        .xnair-toc-sidebar h4 {
            font-size: 15px;
            font-weight: 700;
            color: var(--primary-blue);
            margin-bottom: 14px;
            letter-spacing: 0.3px;
            text-transform: uppercase;
        }
        /* TOC链接：强制上下排列（垂直列表） */
        .xnair-toc-list {
            list-style: none;
            display: flex;
            flex-direction: column;
            gap: 6px;
        }
        .xnair-toc-list li a {
            display: block;
            padding: 7px 10px;
            font-size: 13.5px;
            color: #475569;
            border-left: 2px solid transparent;
            border-radius: 0 4px 4px 0;
            transition: all 0.2s ease;
            line-height: 1.4;
            font-weight: 500;
        }
        .xnair-toc-list li a:hover {
            color: #3399ff;
            background: #eef6ff;
            border-left-color: #3399ff;
        }

        /* 移动端TOC折叠模块 */
        .xnair-toc-mobile-wrap {
            display: none;
            margin: 0 0 20px 0;
            border: 1px solid var(--border-color);
            border-radius: 8px;
            background: #f9fafb;
            overflow: hidden;
        }
        .xnair-toc-mobile-wrap summary {
            padding: 14px 18px;
            font-weight: 700;
            font-size: 15px;
            color: var(--primary-blue);
            cursor: pointer;
            list-style: none;
            display: flex;
            justify-content: space-between;
            align-items: center;
            background: #fff;
            border-bottom: 1px solid transparent;
            user-select: none;
        }
        .xnair-toc-mobile-wrap[open] summary {
            border-bottom-color: var(--border-color);
        }
        .xnair-toc-mobile-wrap summary::after {
            content: '▾';
            font-size: 14px;
            transition: transform 0.25s ease;
            color: #64748b;
        }
        .xnair-toc-mobile-wrap[open] summary::after {
            transform: rotate(180deg);
        }
        .xnair-toc-mobile-inner {
            padding: 12px 18px 16px;
        }
        .xnair-toc-mobile-inner ul {
            list-style: none;
            display: flex;
            flex-direction: column;
            gap: 4px;
        }
        .xnair-toc-mobile-inner ul li a {
            display: block;
            padding: 8px 10px;
            font-size: 14px;
            color: #475569;
            border-radius: 4px;
            font-weight: 500;
        }
        .xnair-toc-mobile-inner ul li a:hover {
            color: #3399ff;
            background: #eef6ff;
        }

        /* xnair Hero区域 */
        .xnair-hero-wrap {
            display: flex;
            gap: 36px;
            align-items: center;
            margin-bottom: 36px;
        }
        .xnair-hero-text {
            flex: 1;
            min-width: 0;
        }
        .xnair-hero-text h1 {
            font-size: 2rem;
            font-weight: 700;
            color: var(--primary-blue);
            line-height: 1.25;
            margin-bottom: 14px;
            letter-spacing: -0.3px;
        }
        .xnair-hero-text .xnair-hero-sub {
            font-size: 1.05rem;
            color: #64748b;
            margin-bottom: 18px;
            line-height: 1.55;
        }
        .xnair-hero-highlights {
            list-style: none;
            display: flex;
            flex-wrap: wrap;
            gap: 10px;
            margin-bottom: 20px;
        }
        .xnair-hero-highlights li {
            background: #eef6ff;
            color: var(--accent-blue);
            padding: 6px 14px;
            border-radius: 20px;
            font-size: 13.5px;
            font-weight: 600;
            white-space: nowrap;
        }
        .xnair-btn-primary {
            display: inline-block;
            background: #3399ff;
            color: #fff;
            padding: 12px 26px;
            border-radius: 6px;
            font-weight: 700;
            font-size: 15px;
            letter-spacing: 0.3px;
            transition: background 0.25s ease;
        }
        .xnair-btn-primary:hover {
            background: #1a7fd4;
            color: #fff;
        }
        .xnair-hero-img {
            flex: 0 0 460px;
            max-width: 460px;
            border-radius: 10px;
            overflow: hidden;
            box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
            background: #f1f5f9;
        }
        .xnair-hero-img img {
            width: 100%;
            height: auto;
            display: block;
        }

        /* xnair AI概述卡片 */
        .xnair-ai-summary {
            background: #f0f7ff;
            border-left: 4px solid #3399ff;
            padding: 18px 22px;
            border-radius: 0 8px 8px 0;
            margin-bottom: 32px;
            font-size: 15px;
            color: #1e3a5f;
            line-height: 1.6;
        }
        .xnair-ai-summary strong {
            color: var(--primary-blue);
        }

        /* xnair 技术规格表 */
        .xnair-specs-table-wrap {
            margin-bottom: 36px;
            overflow-x: auto;
            -webkit-overflow-scrolling: touch;
        }
        .xnair-specs-table {
            width: 100%;
            border-collapse: collapse;
            font-size: 14.5px;
            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: 14px;
            letter-spacing: 0.3px;
            white-space: nowrap;
        }
        .xnair-specs-table tbody td {
            padding: 11px 16px;
            border-bottom: 1px solid var(--border-color);
            vertical-align: top;
        }
        .xnair-specs-table tbody tr:nth-child(even) td {
            background: #f8fafc;
        }
        .xnair-specs-table tbody tr:hover td {
            background: #eef6ff;
        }
        .xnair-specs-table .xnair-spec-label {
            font-weight: 600;
            color: var(--dark-charcoal);
            white-space: nowrap;
        }

        /* xnair H2/H3标题 */
        .xnair-content-area h2 {
            font-size: 1.55rem;
            color: var(--primary-blue);
            margin: 36px 0 14px;
            padding-bottom: 8px;
            border-bottom: 2px solid #e2e8f0;
            letter-spacing: -0.2px;
        }
        .xnair-content-area h2:first-of-type {
            margin-top: 0;
        }
        .xnair-content-area h3 {
            font-size: 1.2rem;
            color: var(--accent-blue);
            margin: 22px 0 10px;
            font-weight: 600;
        }

        /* xnair 图片通用容器 */
        .xnair-img-figure {
            margin: 24px 0;
            border-radius: 8px;
            overflow: hidden;
            background: #f1f5f9;
            box-shadow: 0 4px 16px rgba(0, 0, 0, 0.05);
        }
        .xnair-img-figure img {
            width: 100%;
            display: block;
        }
        .xnair-img-figure figcaption {
            padding: 10px 14px;
            font-size: 13px;
            color: #64748b;
            background: #fff;
            border-top: 1px solid var(--border-color);
            font-style: italic;
        }

        /* xnair 左右图文排版 */
        .xnair-media-row {
            display: flex;
            gap: 28px;
            align-items: flex-start;
            margin: 20px 0;
        }
        .xnair-media-row .xnair-media-img {
            flex: 0 0 320px;
            max-width: 320px;
            border-radius: 8px;
            overflow: hidden;
            box-shadow: 0 4px 16px rgba(0, 0, 0, 0.05);
            background: #f1f5f9;
        }
        .xnair-media-row .xnair-media-img img {
            width: 100%;
            display: block;
        }
        .xnair-media-row .xnair-media-text {
            flex: 1;
            min-width: 0;
        }

        /* xnair 工程细节列表 */
        .xnair-eng-list {
            list-style: none;
            padding: 0;
        }
        .xnair-eng-list li {
            padding: 8px 0 8px 22px;
            position: relative;
            line-height: 1.55;
            font-size: 15px;
            color: #475569;
        }
        .xnair-eng-list li::before {
            content: '◆';
            position: absolute;
            left: 0;
            top: 10px;
            font-size: 10px;
            color: #3399ff;
        }

        /* xnair FAQ样式 */
        .xnair-faq-item {
            border: 1px solid var(--border-color);
            border-radius: 8px;
            margin-bottom: 12px;
            overflow: hidden;
            background: #fff;
        }
        .xnair-faq-item summary {
            padding: 15px 18px;
            font-weight: 600;
            cursor: pointer;
            list-style: none;
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-size: 15px;
            color: var(--dark-charcoal);
            background: #fafbfc;
            user-select: none;
        }
        .xnair-faq-item summary::after {
            content: '+';
            font-size: 20px;
            font-weight: 300;
            color: #64748b;
            transition: transform 0.25s ease;
        }
        .xnair-faq-item[open] summary::after {
            content: '−';
            transform: rotate(0deg);
        }
        .xnair-faq-item .xnair-faq-answer {
            padding: 14px 18px 18px;
            font-size: 14.5px;
            color: #475569;
            line-height: 1.6;
            border-top: 1px solid var(--border-color);
        }

        /* xnair 质量认证模块 */
        .xnair-quality-module {
            background: #f9fafb;
            border: 1px solid var(--border-color);
            border-radius: 10px;
            padding: 28px 24px;
            margin: 32px 0;
        }
        .xnair-quality-module h3 {
            margin-top: 0;
            color: var(--primary-blue);
        }
        .xnair-quality-module p {
            font-size: 14.5px;
            color: #475569;
            line-height: 1.6;
            margin-bottom: 10px;
        }
        .xnair-cert-badges {
            display: flex;
            flex-wrap: wrap;
            gap: 12px;
            margin-top: 14px;
        }
        .xnair-cert-badge {
            background: #fff;
            border: 1px solid #dde4ed;
            border-radius: 6px;
            padding: 8px 16px;
            font-size: 13px;
            font-weight: 600;
            color: var(--accent-blue);
            letter-spacing: 0.2px;
        }

        /* xnair 相关产品卡片 */
        .xnair-related-products {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
            gap: 16px;
            margin: 20px 0 30px;
        }
        .xnair-related-card {
            border: 1px solid var(--border-color);
            border-radius: 8px;
            padding: 16px;
            text-align: center;
            background: #fff;
            transition: box-shadow 0.25s ease;
        }
        .xnair-related-card:hover {
            box-shadow: 0 6px 20px rgba(0, 0, 0, 0.07);
        }
        .xnair-related-card a {
            font-weight: 600;
            color: var(--accent-blue);
            font-size: 14.5px;
        }
        .xnair-related-card a:hover {
            color: #3399ff;
            text-decoration: underline;
        }

        /* xnair 上一篇/下一篇导航 */
        .xnair-pagination-nav {
            display: flex;
            justify-content: space-between;
            gap: 16px;
            margin-top: 36px;
            padding-top: 20px;
            border-top: 1px solid var(--border-color);
            flex-wrap: wrap;
        }
        .xnair-pagination-nav a {
            display: inline-flex;
            align-items: center;
            gap: 6px;
            font-weight: 600;
            font-size: 14.5px;
            color: var(--accent-blue);
            padding: 8px 14px;
            border: 1px solid var(--border-color);
            border-radius: 6px;
            transition: all 0.25s ease;
        }
        .xnair-pagination-nav a:hover {
            background: #eef6ff;
            border-color: #3399ff;
            color: #3399ff;
        }

        /* xnair 联系CTA条 */
        .xnair-cta-bar {
            background: var(--primary-blue);
            color: #fff;
            padding: 20px 24px;
            border-radius: 8px;
            text-align: center;
            margin: 28px 0;
            font-size: 15px;
        }
        .xnair-cta-bar a {
            color: #ffd54f;
            font-weight: 700;
            text-decoration: underline;
            margin-left: 6px;
        }
        .xnair-cta-bar a:hover {
            color: #fff;
        }

        /* ========== xnair 响应式：平板端 ========== */
        @media(max-width: 1024px) {
            .xnair-main-wrapper {
                gap: 24px;
            }
            .xnair-toc-sidebar {
                width: 220px;
                padding: 16px 14px;
                font-size: 13px;
            }
            .xnair-hero-wrap {
                gap: 20px;
            }
            .xnair-hero-img {
                flex: 0 0 340px;
                max-width: 340px;
            }
            .xnair-hero-text h1 {
                font-size: 1.6rem;
            }
            .xnair-media-row .xnair-media-img {
                flex: 0 0 240px;
                max-width: 240px;
            }
        }

        /* ========== xnair 响应式：移动端768px ========== */
        @media(max-width: 768px) {
            .xnair-main-wrapper {
                flex-direction: column;
                gap: 0;
                padding: 20px 0 30px;
            }
            /* 桌面TOC侧边栏在移动端隐藏 */
            .xnair-toc-sidebar {
                display: none;
            }
            /* 移动端折叠TOC显示 */
            .xnair-toc-mobile-wrap {
                display: block;
            }
            .xnair-hero-wrap {
                flex-direction: column-reverse;
                gap: 16px;
            }
            .xnair-hero-img {
                flex: 0 0 auto;
                max-width: 100%;
                width: 100%;
            }
            .xnair-hero-text h1 {
                font-size: 1.4rem;
            }
            .xnair-hero-text .xnair-hero-sub {
                font-size: 0.95rem;
            }
            .xnair-media-row {
                flex-direction: column;
                gap: 12px;
            }
            .xnair-media-row .xnair-media-img {
                flex: 0 0 auto;
                max-width: 100%;
                width: 100%;
            }
            .xnair-specs-table {
                font-size: 13px;
                min-width: 480px;
            }
            .xnair-content-area h2 {
                font-size: 1.3rem;
            }
            .xnair-content-area h3 {
                font-size: 1.05rem;
            }
            .xnair-related-products {
                grid-template-columns: 1fr 1fr;
            }
            .xnair-pagination-nav {
                flex-direction: column;
                gap: 10px;
            }
            .xnair-pagination-nav a {
                justify-content: center;
            }
            .xnair-hero-highlights li {
                font-size: 12px;
                padding: 5px 10px;
            }
        }
        @media(max-width: 480px) {
            .xnair-hero-text h1 {
                font-size: 1.2rem;
            }
            .xnair-hero-highlights {
                gap: 6px;
            }
            .xnair-hero-highlights li {
                font-size: 11px;
                padding: 4px 8px;
            }
            .xnair-related-products {
                grid-template-columns: 1fr;
            }
            .xnair-specs-table {
                min-width: 380px;
                font-size: 12px;
            }
        }