/* ========== 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;
            }
            .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;
        }
        @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 CSS 变量扩展 ========== */
        :root {
            --xnair-slate: #1e293b;
            --xnair-gray-light: #f8fafc;
            --xnair-accent-teal: #0d9488;
            --xnair-warm-border: #e4e7eb;
            --xnair-table-stripe: #f1f5f9;
            --xnair-highlight-gold: #b8860b;
            --xnair-surface-card: #ffffff;
            --xnair-shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06);
            --xnair-shadow-md: 0 4px 16px rgba(0, 0, 0, 0.08);
            --xnair-radius: 8px;
        }

        /* ========== 产品页全局容器微调 ========== */
        .xnair-product-wrap {
            max-width: 1440px;
            margin: 0 auto;
            padding: 0 40px;
        }

        /* ========== 面包屑导航（产品页专用） ========== */
        .xnair-breadcrumb {
            padding: 18px 0 10px;
            font-size: 14px;
            color: #64748b;
            border-bottom: 1px solid var(--xnair-warm-border);
            margin-bottom: 0;
            background: #fafbfc;
        }
        .xnair-breadcrumb ol {
            list-style: none;
            display: flex;
            flex-wrap: wrap;
            gap: 6px;
            align-items: center;
            padding: 0;
            margin: 0;
        }
        .xnair-breadcrumb ol li {
            display: inline-flex;
            align-items: center;
        }
        .xnair-breadcrumb ol li+li::before {
            content: "/";
            margin-right: 6px;
            color: #c0c7cf;
            font-weight: 400;
        }
        .xnair-breadcrumb ol li a {
            color: #475569;
            font-weight: 500;
            transition: color 0.2s;
        }
        .xnair-breadcrumb ol li a:hover {
            color: var(--accent-blue);
            text-decoration: underline;
        }
        .xnair-breadcrumb ol li:last-child {
            color: var(--xnair-slate);
            font-weight: 600;
        }

        /* ========== 产品页两栏布局（桌面端：TOC侧边栏 + 主内容） ========== */
        .xnair-content-grid {
            display: grid;
            grid-template-columns: 240px 1fr;
            gap: 44px;
            align-items: start;
            margin-top: 28px;
            margin-bottom: 50px;
        }

        /* ========== TOC 悬浮目录（垂直排列，sticky悬浮） ========== */
        .xnair-toc-sidebar {
            position: sticky;
            top: 100px;
            background: var(--xnair-surface-card);
            border: 1px solid var(--xnair-warm-border);
            border-radius: var(--xnair-radius);
            padding: 22px 18px;
            box-shadow: var(--xnair-shadow-sm);
            z-index: 50;
            max-height: calc(100vh - 140px);
            overflow-y: auto;
        }
        .xnair-toc-title {
            font-size: 15px;
            font-weight: 700;
            color: var(--xnair-slate);
            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;
            padding: 0;
            margin: 0;
            display: flex;
            flex-direction: column;
            gap: 4px;
        }
        .xnair-toc-list li {
            margin: 0;
            padding: 0;
        }
        .xnair-toc-list li a {
            display: block;
            padding: 8px 10px;
            font-size: 14px;
            color: #475569;
            border-left: 3px solid transparent;
            border-radius: 4px;
            transition: all 0.2s ease;
            font-weight: 500;
            line-height: 1.4;
        }
        .xnair-toc-list li a:hover,
        .xnair-toc-list li a.xnair-toc-active {
            color: var(--accent-blue);
            background: #eff6ff;
            border-left-color: var(--accent-blue);
            font-weight: 600;
        }
        /* 移动端TOC折叠按钮 */
        .xnair-toc-toggle-btn {
            display: none;
            width: 100%;
            padding: 12px 16px;
            background: var(--accent-blue);
            color: #fff;
            border: none;
            border-radius: var(--xnair-radius);
            font-size: 15px;
            font-weight: 600;
            cursor: pointer;
            text-align: left;
            position: relative;
        }
        .xnair-toc-toggle-btn::after {
            content: "▾";
            position: absolute;
            right: 16px;
            top: 50%;
            transform: translateY(-50%);
            font-size: 14px;
            transition: transform 0.3s;
        }
        .xnair-toc-toggle-btn.xnair-open::after {
            transform: translateY(-50%) rotate(180deg);
        }
        .xnair-toc-collapsible {
            overflow: hidden;
            transition: max-height 0.4s ease;
        }

        /* ========== Hero 区域 ========== */
        .xnair-hero-wrap {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 40px;
            align-items: center;
            background: linear-gradient(135deg, #f9fafb 0%, #eef2f7 100%);
            border-radius: 12px;
            padding: 36px;
            border: 1px solid var(--xnair-warm-border);
            box-shadow: var(--xnair-shadow-md);
        }
        .xnair-hero-text h1 {
            font-size: 30px;
            font-weight: 700;
            color: var(--xnair-slate);
            line-height: 1.25;
            margin-bottom: 14px;
            letter-spacing: -0.3px;
        }
        .xnair-hero-text .xnair-hero-subtitle {
            font-size: 17px;
            color: #475569;
            margin-bottom: 8px;
            font-weight: 500;
        }
        .xnair-hero-text .xnair-hero-specs-row {
            display: flex;
            flex-wrap: wrap;
            gap: 16px;
            margin-top: 16px;
        }
        .xnair-hero-spec-badge {
            background: #fff;
            border: 1px solid var(--xnair-warm-border);
            border-radius: 6px;
            padding: 8px 14px;
            font-size: 13px;
            font-weight: 600;
            color: var(--xnair-slate);
            white-space: nowrap;
            box-shadow: var(--xnair-shadow-sm);
        }
        .xnair-hero-image img {
            border-radius: 8px;
            width: 100%;
            height: auto;
            object-fit: contain;
            background: #fff;
            padding: 12px;
            border: 1px solid var(--xnair-warm-border);
        }
        .xnair-hero-cta {
            display: inline-block;
            margin-top: 18px;
            padding: 12px 28px;
            background: var(--accent-blue);
            color: #fff;
            font-weight: 700;
            font-size: 15px;
            border-radius: 6px;
            letter-spacing: 0.3px;
            transition: background 0.25s;
        }
        .xnair-hero-cta:hover {
            background: #0d365e;
            color: #fff;
        }

        /* ========== AI Overview 摘要卡片 ========== */
        .xnair-overview-card {
            background: #f0f7ff;
            border-left: 5px solid var(--accent-blue);
            padding: 20px 24px;
            border-radius: 0 var(--xnair-radius) var(--xnair-radius) 0;
            margin: 28px 0;
            font-size: 15px;
            color: #334155;
            line-height: 1.7;
            box-shadow: var(--xnair-shadow-sm);
        }
        .xnair-overview-card strong {
            color: var(--xnair-slate);
        }

        /* ========== 技术规格表 ========== */
        .xnair-specs-table-wrap {
            overflow-x: auto;
            margin: 28px 0;
            border-radius: var(--xnair-radius);
            border: 1px solid var(--xnair-warm-border);
            box-shadow: var(--xnair-shadow-sm);
        }
        .xnair-specs-table {
            width: 100%;
            border-collapse: collapse;
            font-size: 14px;
            min-width: 700px;
        }
        .xnair-specs-table thead th {
            background: var(--xnair-slate);
            color: #fff;
            padding: 14px 16px;
            text-align: left;
            font-weight: 600;
            font-size: 13px;
            letter-spacing: 0.4px;
            text-transform: uppercase;
        }
        .xnair-specs-table tbody td {
            padding: 12px 16px;
            border-bottom: 1px solid var(--xnair-warm-border);
            vertical-align: top;
        }
        .xnair-specs-table tbody tr:nth-child(even) td {
            background: var(--xnair-table-stripe);
        }
        .xnair-specs-table tbody tr:hover td {
            background: #e8f0fb;
        }
        .xnair-specs-table .xnair-spec-label {
            font-weight: 700;
            color: var(--xnair-slate);
            width: 220px;
            min-width: 180px;
        }

        /* ========== 通用内容区块标题 ========== */
        .xnair-section-title {
            font-size: 24px;
            font-weight: 700;
            color: var(--xnair-slate);
            margin: 36px 0 16px;
            padding-bottom: 10px;
            border-bottom: 3px solid var(--accent-blue);
            display: inline-block;
            letter-spacing: -0.2px;
        }
        .xnair-section-subtitle {
            font-size: 19px;
            font-weight: 700;
            color: #334155;
            margin: 22px 0 10px;
        }

        /* ========== 四类工业图片通用卡片样式 ========== */
        .xnair-image-card {
            background: #fff;
            border: 1px solid var(--xnair-warm-border);
            border-radius: var(--xnair-radius);
            padding: 18px;
            margin: 20px 0;
            box-shadow: var(--xnair-shadow-sm);
            text-align: center;
        }
        .xnair-image-card img {
            border-radius: 6px;
            width: 100%;
            height: auto;
            object-fit: cover;
            max-height: 420px;
            background: #f9fafb;
        }
        .xnair-image-card .xnair-image-caption {
            font-size: 13px;
            color: #64748b;
            margin-top: 10px;
            font-style: italic;
            line-height: 1.5;
        }

        /* ========== 全球适应性 H3 分区卡片 ========== */
        .xnair-region-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 20px;
            margin: 20px 0;
        }
        .xnair-region-card {
            background: #fff;
            border: 1px solid var(--xnair-warm-border);
            border-radius: var(--xnair-radius);
            padding: 20px;
            box-shadow: var(--xnair-shadow-sm);
            transition: box-shadow 0.25s;
        }
        .xnair-region-card:hover {
            box-shadow: var(--xnair-shadow-md);
        }
        .xnair-region-card h3 {
            font-size: 17px;
            font-weight: 700;
            color: var(--accent-blue);
            margin-bottom: 8px;
        }
        .xnair-region-card p {
            font-size: 14px;
            color: #475569;
            line-height: 1.65;
        }

        /* ========== 工程细节列表 ========== */
        .xnair-eng-list {
            list-style: none;
            padding: 0;
            margin: 16px 0;
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 10px;
        }
        .xnair-eng-list li {
            background: #fff;
            border: 1px solid var(--xnair-warm-border);
            border-radius: 6px;
            padding: 12px 16px;
            font-size: 14px;
            color: #334155;
            position: relative;
            padding-left: 34px;
            box-shadow: var(--xnair-shadow-sm);
        }
        .xnair-eng-list li::before {
            content: "●";
            position: absolute;
            left: 14px;
            top: 12px;
            color: var(--accent-blue);
            font-weight: 700;
            font-size: 16px;
        }

        /* ========== FAQ 区域 ========== */
        .xnair-faq-item {
            border: 1px solid var(--xnair-warm-border);
            border-radius: var(--xnair-radius);
            margin-bottom: 12px;
            overflow: hidden;
            box-shadow: var(--xnair-shadow-sm);
        }
        .xnair-faq-question {
            background: #f9fafb;
            padding: 16px 20px;
            font-weight: 700;
            font-size: 15px;
            color: var(--xnair-slate);
            cursor: pointer;
            user-select: none;
            position: relative;
            padding-right: 40px;
            transition: background 0.2s;
        }
        .xnair-faq-question::after {
            content: "+";
            position: absolute;
            right: 18px;
            top: 50%;
            transform: translateY(-50%);
            font-size: 20px;
            font-weight: 700;
            color: var(--accent-blue);
            transition: transform 0.3s;
        }
        .xnair-faq-item.xnair-faq-open .xnair-faq-question::after {
            content: "−";
            transform: translateY(-50%);
        }
        .xnair-faq-answer {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.4s ease, padding 0.4s ease;
            padding: 0 20px;
            font-size: 14px;
            color: #475569;
            line-height: 1.7;
            background: #fff;
        }
        .xnair-faq-item.xnair-faq-open .xnair-faq-answer {
            max-height: 300px;
            padding: 14px 20px;
        }

        /* ========== 品质认证模块 ========== */
        .xnair-quality-wrap {
            background: #fafdf9;
            border: 2px solid #d1e7d6;
            border-radius: var(--xnair-radius);
            padding: 28px;
            margin: 28px 0;
            box-shadow: var(--xnair-shadow-sm);
        }
        .xnair-quality-wrap h2 {
            color: #2d6a4f;
            font-size: 22px;
            margin-bottom: 14px;
        }
        .xnair-quality-wrap p {
            font-size: 14px;
            color: #334155;
            line-height: 1.7;
        }
        .xnair-cert-badges {
            display: flex;
            flex-wrap: wrap;
            gap: 12px;
            margin-top: 16px;
        }
        .xnair-cert-badge {
            display: inline-block;
            background: #fff;
            border: 1px solid #c8dfd0;
            border-radius: 20px;
            padding: 6px 16px;
            font-size: 13px;
            font-weight: 600;
            color: #2d6a4f;
        }

        /* ========== 上一篇/下一篇 导航 ========== */
        .xnair-pagination-nav {
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
            gap: 16px;
            padding: 24px 0;
            margin: 32px 0;
            border-top: 2px solid var(--xnair-warm-border);
            border-bottom: 2px solid var(--xnair-warm-border);
        }
        .xnair-pagination-nav a {
            display: inline-flex;
            align-items: center;
            gap: 6px;
            font-weight: 600;
            font-size: 14px;
            color: var(--accent-blue);
            padding: 8px 16px;
            border: 1px solid var(--xnair-warm-border);
            border-radius: 6px;
            transition: all 0.25s;
            background: #fff;
        }
        .xnair-pagination-nav a:hover {
            background: #eff6ff;
            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;
        }

        /* ========== 相关产品推荐 ========== */
        .xnair-related-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 20px;
            margin: 20px 0 30px;
        }
        .xnair-related-card {
            background: #fff;
            border: 1px solid var(--xnair-warm-border);
            border-radius: var(--xnair-radius);
            padding: 18px;
            text-align: center;
            box-shadow: var(--xnair-shadow-sm);
            transition: box-shadow 0.25s;
        }
        .xnair-related-card:hover {
            box-shadow: var(--xnair-shadow-md);
        }
        .xnair-related-card img {
            border-radius: 6px;
            margin-bottom: 10px;
            height: 160px;
            object-fit: contain;
            background: #f9fafb;
            width: 100%;
        }
        .xnair-related-card a {
            font-weight: 600;
            font-size: 14px;
            color: var(--accent-blue);
        }
        .xnair-related-card a:hover {
            text-decoration: underline;
        }

        /* ========== 响应式适配（产品页） ========== */
        @media(max-width: 1100px) {
            .xnair-content-grid {
                grid-template-columns: 200px 1fr;
                gap: 28px;
            }
            .xnair-hero-wrap {
                grid-template-columns: 1fr;
                gap: 24px;
            }
            .xnair-region-grid {
                grid-template-columns: 1fr 1fr;
            }
            .xnair-eng-list {
                grid-template-columns: 1fr;
            }
            .xnair-related-grid {
                grid-template-columns: 1fr 1fr;
            }
        }
        @media(max-width: 768px) {
            .xnair-product-wrap {
                padding: 0 20px;
            }
            /* TOC 移动端折叠 */
            .xnair-content-grid {
                grid-template-columns: 1fr;
                gap: 0;
            }
            .xnair-toc-sidebar {
                position: static;
                border: none;
                box-shadow: none;
                padding: 0;
                margin-bottom: 16px;
                background: transparent;
                max-height: none;
                overflow: visible;
            }
            .xnair-toc-title {
                display: none;
            }
            .xnair-toc-toggle-btn {
                display: block;
            }
            .xnair-toc-collapsible {
                max-height: 0;
                border: 1px solid var(--xnair-warm-border);
                border-radius: var(--xnair-radius);
                background: #fff;
                margin-top: 6px;
            }
            .xnair-toc-collapsible.xnair-open {
                max-height: 500px;
            }
            .xnair-toc-list {
                padding: 12px 14px;
            }
            .xnair-hero-wrap {
                padding: 20px;
                gap: 16px;
            }
            .xnair-hero-text h1 {
                font-size: 24px;
            }
            .xnair-region-grid {
                grid-template-columns: 1fr;
            }
            .xnair-related-grid {
                grid-template-columns: 1fr;
            }
            .xnair-pagination-nav {
                flex-direction: column;
                align-items: stretch;
            }
            .xnair-pagination-nav a {
                justify-content: center;
            }
            .xnair-specs-table {
                font-size: 12px;
            }
            .xnair-specs-table .xnair-spec-label {
                width: 140px;
                min-width: 120px;
            }
        }
        @media(max-width: 480px) {
            .xnair-hero-text h1 {
                font-size: 20px;
            }
            .xnair-hero-text .xnair-hero-specs-row {
                gap: 8px;
            }
            .xnair-hero-spec-badge {
                font-size: 11px;
                padding: 6px 10px;
            }
            .xnair-section-title {
                font-size: 20px;
            }
            .xnair-quality-wrap {
                padding: 16px;
            }
        }