/* roulang page: index */
/* ===== Design Variables ===== */
    :root {
        --primary: #1e3a5f;
        --primary-light: #2d5f8a;
        --primary-dark: #0f2440;
        --secondary: #2d7dd2;
        --secondary-light: #4a9af0;
        --accent: #f0a500;
        --accent-light: #ffc233;
        --accent-dark: #c98800;
        --bg: #f8fafc;
        --bg-alt: #edf2f7;
        --bg-dark: #0f1a2e;
        --text: #1a202c;
        --text-light: #64748b;
        --text-white: #f1f5f9;
        --border: #e2e8f0;
        --border-light: #f1f5f9;
        --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
        --shadow: 0 4px 20px rgba(0,0,0,0.08);
        --shadow-lg: 0 12px 40px rgba(0,0,0,0.12);
        --radius-sm: 6px;
        --radius: 12px;
        --radius-lg: 20px;
        --radius-full: 50px;
        --font: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
        --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
        --nav-width: 260px;
        --nav-collapsed: 72px;
        --header-height: 0px;
    }

    /* ===== Reset & Base ===== */
    *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
    html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }
    body {
        font-family: var(--font);
        color: var(--text);
        background: var(--bg);
        line-height: 1.6;
        font-size: 16px;
        display: flex;
        min-height: 100vh;
    }
    a { color: inherit; text-decoration: none; transition: var(--transition); }
    a:hover { color: var(--secondary); }
    img { max-width: 100%; height: auto; display: block; border-radius: var(--radius-sm); }
    button, input, select, textarea { font-family: inherit; font-size: inherit; }
    ul, ol { list-style: none; }
    h1, h2, h3, h4, h5, h6 { line-height: 1.25; font-weight: 700; color: var(--text); }
    ::selection { background: var(--secondary); color: #fff; }
    :focus-visible { outline: 2px solid var(--secondary); outline-offset: 2px; }

    /* ===== Container ===== */
    .container { width: 100%; max-width: 1200px; margin: 0 auto; padding: 0 24px; }
    .container-wide { max-width: 1400px; }

    /* ===== Left App Shell Navigation ===== */
    .app-shell {
        display: flex;
        width: 100%;
        min-height: 100vh;
    }
    .side-nav {
        position: fixed;
        top: 0;
        left: 0;
        width: var(--nav-width);
        height: 100vh;
        background: var(--primary-dark);
        color: var(--text-white);
        display: flex;
        flex-direction: column;
        z-index: 1000;
        transition: width var(--transition), transform var(--transition);
        overflow-y: auto;
        overflow-x: hidden;
        box-shadow: 2px 0 20px rgba(0,0,0,0.15);
    }
    .side-nav .nav-brand {
        display: flex;
        align-items: center;
        gap: 12px;
        padding: 28px 24px 20px;
        border-bottom: 1px solid rgba(255,255,255,0.08);
    }
    .side-nav .nav-brand .brand-icon {
        width: 42px;
        height: 42px;
        background: var(--secondary);
        border-radius: var(--radius);
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 22px;
        font-weight: 800;
        color: #fff;
        flex-shrink: 0;
    }
    .side-nav .nav-brand .brand-text {
        font-size: 20px;
        font-weight: 700;
        color: #fff;
        letter-spacing: 0.5px;
        white-space: nowrap;
    }
    .side-nav .nav-brand .brand-text span { color: var(--accent); }
    .side-nav .nav-items {
        padding: 16px 12px;
        flex: 1;
        display: flex;
        flex-direction: column;
        gap: 4px;
    }
    .side-nav .nav-items .nav-item {
        display: flex;
        align-items: center;
        gap: 14px;
        padding: 12px 16px;
        border-radius: var(--radius);
        color: rgba(255,255,255,0.7);
        font-weight: 500;
        font-size: 15px;
        transition: var(--transition);
        cursor: pointer;
        white-space: nowrap;
    }
    .side-nav .nav-items .nav-item i {
        width: 22px;
        text-align: center;
        font-size: 18px;
        flex-shrink: 0;
    }
    .side-nav .nav-items .nav-item:hover {
        background: rgba(255,255,255,0.08);
        color: #fff;
    }
    .side-nav .nav-items .nav-item.active {
        background: var(--secondary);
        color: #fff;
        box-shadow: 0 4px 12px rgba(45,125,210,0.3);
    }
    .side-nav .nav-footer {
        padding: 16px 20px 24px;
        border-top: 1px solid rgba(255,255,255,0.08);
        font-size: 12px;
        color: rgba(255,255,255,0.4);
        text-align: center;
        white-space: nowrap;
    }

    /* ===== Main Content Area ===== */
    .main-content {
        margin-left: var(--nav-width);
        flex: 1;
        min-height: 100vh;
        display: flex;
        flex-direction: column;
        transition: margin-left var(--transition);
    }

    /* ===== Mobile Header ===== */
    .mobile-header {
        display: none;
        position: sticky;
        top: 0;
        z-index: 999;
        background: var(--primary-dark);
        color: #fff;
        padding: 12px 20px;
        align-items: center;
        justify-content: space-between;
        box-shadow: 0 2px 12px rgba(0,0,0,0.15);
    }
    .mobile-header .mobile-brand {
        display: flex;
        align-items: center;
        gap: 10px;
        font-size: 18px;
        font-weight: 700;
        color: #fff;
    }
    .mobile-header .mobile-brand .brand-icon {
        width: 34px;
        height: 34px;
        background: var(--secondary);
        border-radius: var(--radius-sm);
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 16px;
        font-weight: 800;
        color: #fff;
    }
    .mobile-header .mobile-brand span { color: var(--accent); }
    .mobile-header .menu-toggle {
        background: none;
        border: none;
        color: #fff;
        font-size: 24px;
        cursor: pointer;
        padding: 4px 8px;
        border-radius: var(--radius-sm);
        transition: var(--transition);
    }
    .mobile-header .menu-toggle:hover { background: rgba(255,255,255,0.1); }

    /* Mobile overlay */
    .nav-overlay {
        display: none;
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background: rgba(0,0,0,0.5);
        z-index: 999;
        opacity: 0;
        transition: opacity var(--transition);
    }
    .nav-overlay.show { opacity: 1; }

    /* ===== Hero Section ===== */
    .hero {
        position: relative;
        padding: 100px 0 80px;
        background: var(--primary-dark);
        color: #fff;
        overflow: hidden;
        min-height: 520px;
        display: flex;
        align-items: center;
    }
    .hero::before {
        content: '';
        position: absolute;
        inset: 0;
        background: url('/assets/images/backpic/back-1.png') center center / cover no-repeat;
        opacity: 0.25;
        z-index: 0;
    }
    .hero::after {
        content: '';
        position: absolute;
        inset: 0;
        background: linear-gradient(135deg, rgba(15,36,64,0.92) 0%, rgba(30,58,95,0.75) 100%);
        z-index: 1;
    }
    .hero .container { position: relative; z-index: 2; }
    .hero .hero-grid {
        display: grid;
        grid-template-columns: 1fr 1fr;
        gap: 60px;
        align-items: center;
    }
    .hero .hero-badge {
        display: inline-flex;
        align-items: center;
        gap: 8px;
        background: rgba(45,125,210,0.2);
        border: 1px solid rgba(45,125,210,0.3);
        color: var(--accent-light);
        padding: 6px 16px;
        border-radius: var(--radius-full);
        font-size: 13px;
        font-weight: 600;
        margin-bottom: 20px;
        letter-spacing: 0.3px;
    }
    .hero .hero-badge i { font-size: 14px; }
    .hero h1 {
        font-size: 44px;
        font-weight: 800;
        line-height: 1.15;
        color: #fff;
        margin-bottom: 20px;
        letter-spacing: -0.5px;
    }
    .hero h1 span { color: var(--accent); }
    .hero .hero-sub {
        font-size: 18px;
        color: rgba(255,255,255,0.75);
        line-height: 1.7;
        margin-bottom: 32px;
        max-width: 540px;
    }
    .hero .hero-actions {
        display: flex;
        flex-wrap: wrap;
        gap: 16px;
        align-items: center;
    }
    .hero .hero-stats {
        display: grid;
        grid-template-columns: repeat(3, 1fr);
        gap: 20px;
        padding: 32px;
        background: rgba(255,255,255,0.06);
        border-radius: var(--radius-lg);
        border: 1px solid rgba(255,255,255,0.08);
        backdrop-filter: blur(8px);
    }
    .hero .hero-stats .stat-item { text-align: center; }
    .hero .hero-stats .stat-number {
        font-size: 36px;
        font-weight: 800;
        color: var(--accent);
        line-height: 1;
        margin-bottom: 6px;
    }
    .hero .hero-stats .stat-label {
        font-size: 14px;
        color: rgba(255,255,255,0.6);
        font-weight: 400;
    }

    /* ===== Buttons ===== */
    .btn {
        display: inline-flex;
        align-items: center;
        gap: 8px;
        padding: 12px 28px;
        border-radius: var(--radius-full);
        font-weight: 600;
        font-size: 15px;
        border: none;
        cursor: pointer;
        transition: var(--transition);
        text-align: center;
        justify-content: center;
        white-space: nowrap;
    }
    .btn-primary {
        background: var(--secondary);
        color: #fff;
        box-shadow: 0 4px 14px rgba(45,125,210,0.35);
    }
    .btn-primary:hover { background: var(--secondary-light); transform: translateY(-2px); box-shadow: 0 8px 24px rgba(45,125,210,0.4); color: #fff; }
    .btn-outline {
        background: transparent;
        color: #fff;
        border: 2px solid rgba(255,255,255,0.25);
    }
    .btn-outline:hover { background: rgba(255,255,255,0.1); border-color: rgba(255,255,255,0.5); color: #fff; transform: translateY(-2px); }
    .btn-accent {
        background: var(--accent);
        color: var(--primary-dark);
        box-shadow: 0 4px 14px rgba(240,165,0,0.35);
    }
    .btn-accent:hover { background: var(--accent-light); transform: translateY(-2px); box-shadow: 0 8px 24px rgba(240,165,0,0.4); color: var(--primary-dark); }
    .btn-lg { padding: 16px 36px; font-size: 17px; }
    .btn-sm { padding: 8px 18px; font-size: 13px; }

    /* ===== Section Common ===== */
    .section { padding: 80px 0; }
    .section-alt { background: var(--bg-alt); }
    .section-dark { background: var(--bg-dark); color: var(--text-white); }
    .section-header { text-align: center; margin-bottom: 52px; }
    .section-header .section-label {
        display: inline-block;
        font-size: 13px;
        font-weight: 700;
        text-transform: uppercase;
        letter-spacing: 2px;
        color: var(--secondary);
        margin-bottom: 12px;
    }
    .section-header h2 {
        font-size: 36px;
        font-weight: 800;
        margin-bottom: 16px;
        letter-spacing: -0.3px;
    }
    .section-header h2 span { color: var(--secondary); }
    .section-header .section-desc {
        font-size: 17px;
        color: var(--text-light);
        max-width: 640px;
        margin: 0 auto;
        line-height: 1.7;
    }
    .section-dark .section-header .section-desc { color: rgba(255,255,255,0.65); }
    .section-dark .section-header h2 { color: #fff; }

    /* ===== Features / Cards Grid ===== */
    .features-grid {
        display: grid;
        grid-template-columns: repeat(3, 1fr);
        gap: 28px;
    }
    .feature-card {
        background: #fff;
        border-radius: var(--radius);
        padding: 36px 28px;
        box-shadow: var(--shadow-sm);
        border: 1px solid var(--border);
        transition: var(--transition);
        position: relative;
        overflow: hidden;
    }
    .feature-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: var(--secondary); }
    .feature-card .card-icon {
        width: 56px;
        height: 56px;
        border-radius: var(--radius);
        background: rgba(45,125,210,0.1);
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 24px;
        color: var(--secondary);
        margin-bottom: 20px;
        transition: var(--transition);
    }
    .feature-card:hover .card-icon { background: var(--secondary); color: #fff; }
    .feature-card h3 { font-size: 20px; margin-bottom: 12px; font-weight: 700; }
    .feature-card p { font-size: 15px; color: var(--text-light); line-height: 1.7; }
    .feature-card .card-link {
        display: inline-flex;
        align-items: center;
        gap: 6px;
        margin-top: 18px;
        font-weight: 600;
        color: var(--secondary);
        font-size: 14px;
    }
    .feature-card .card-link:hover { gap: 10px; }

    /* ===== Cover Cards ===== */
    .cover-cards {
        display: grid;
        grid-template-columns: repeat(2, 1fr);
        gap: 28px;
    }
    .cover-card {
        border-radius: var(--radius);
        overflow: hidden;
        background: #fff;
        box-shadow: var(--shadow-sm);
        border: 1px solid var(--border);
        transition: var(--transition);
        display: flex;
        flex-direction: column;
    }
    .cover-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
    .cover-card .card-img {
        width: 100%;
        height: 220px;
        object-fit: cover;
        border-radius: 0;
    }
    .cover-card .card-body { padding: 24px; flex: 1; display: flex; flex-direction: column; }
    .cover-card .card-tag {
        display: inline-block;
        font-size: 12px;
        font-weight: 600;
        color: var(--secondary);
        background: rgba(45,125,210,0.08);
        padding: 3px 12px;
        border-radius: var(--radius-full);
        margin-bottom: 10px;
        align-self: flex-start;
        text-transform: uppercase;
        letter-spacing: 0.5px;
    }
    .cover-card h3 { font-size: 20px; margin-bottom: 10px; font-weight: 700; }
    .cover-card p { font-size: 14px; color: var(--text-light); line-height: 1.7; flex: 1; }
    .cover-card .card-footer { margin-top: 16px; display: flex; align-items: center; gap: 12px; }
    .cover-card .card-footer .btn { font-size: 13px; padding: 8px 20px; }

    /* ===== CMS Content List ===== */
    .content-list { display: flex; flex-direction: column; gap: 16px; }
    .content-item {
        display: flex;
        align-items: center;
        gap: 20px;
        padding: 20px 24px;
        background: #fff;
        border-radius: var(--radius);
        border: 1px solid var(--border);
        transition: var(--transition);
        cursor: default;
    }
    .content-item:hover { border-color: var(--secondary); box-shadow: var(--shadow-sm); transform: translateX(4px); }
    .content-item .item-index {
        width: 40px;
        height: 40px;
        border-radius: var(--radius-sm);
        background: rgba(45,125,210,0.08);
        display: flex;
        align-items: center;
        justify-content: center;
        font-weight: 700;
        color: var(--secondary);
        font-size: 16px;
        flex-shrink: 0;
    }
    .content-item .item-body { flex: 1; min-width: 0; }
    .content-item .item-title {
        font-size: 16px;
        font-weight: 600;
        margin-bottom: 4px;
        display: -webkit-box;
        -webkit-line-clamp: 1;
        -webkit-box-orient: vertical;
        overflow: hidden;
    }
    .content-item .item-title a { color: var(--text); }
    .content-item .item-title a:hover { color: var(--secondary); }
    .content-item .item-meta {
        font-size: 13px;
        color: var(--text-light);
        display: flex;
        align-items: center;
        gap: 12px;
        flex-wrap: wrap;
    }
    .content-item .item-meta .cat-badge {
        display: inline-block;
        font-size: 11px;
        font-weight: 600;
        color: var(--secondary);
        background: rgba(45,125,210,0.08);
        padding: 2px 10px;
        border-radius: var(--radius-full);
    }
    .content-item .item-arrow {
        color: var(--text-light);
        font-size: 18px;
        flex-shrink: 0;
        transition: var(--transition);
    }
    .content-item:hover .item-arrow { color: var(--secondary); transform: translateX(4px); }

    .empty-list {
        text-align: center;
        padding: 48px 24px;
        color: var(--text-light);
        font-size: 16px;
        background: #fff;
        border-radius: var(--radius);
        border: 1px dashed var(--border);
    }
    .empty-list i { font-size: 36px; color: var(--border); margin-bottom: 12px; display: block; }

    /* ===== Testimonials / Trust ===== */
    .trust-grid {
        display: grid;
        grid-template-columns: repeat(4, 1fr);
        gap: 24px;
    }
    .trust-item {
        background: rgba(255,255,255,0.05);
        border: 1px solid rgba(255,255,255,0.08);
        border-radius: var(--radius);
        padding: 28px 20px;
        text-align: center;
        transition: var(--transition);
    }
    .trust-item:hover { background: rgba(255,255,255,0.08); transform: translateY(-2px); }
    .trust-item .trust-number {
        font-size: 32px;
        font-weight: 800;
        color: var(--accent);
        margin-bottom: 6px;
    }
    .trust-item .trust-label { font-size: 14px; color: rgba(255,255,255,0.6); }

    /* ===== FAQ ===== */
    .faq-grid { max-width: 800px; margin: 0 auto; display: flex; flex-direction: column; gap: 12px; }
    .faq-item {
        background: #fff;
        border: 1px solid var(--border);
        border-radius: var(--radius);
        overflow: hidden;
        transition: var(--transition);
    }
    .faq-item:hover { border-color: var(--secondary); }
    .faq-item .faq-question {
        display: flex;
        align-items: center;
        justify-content: space-between;
        padding: 20px 24px;
        font-weight: 600;
        font-size: 16px;
        cursor: pointer;
        gap: 16px;
        user-select: none;
        transition: var(--transition);
    }
    .faq-item .faq-question:hover { color: var(--secondary); }
    .faq-item .faq-question i {
        font-size: 16px;
        color: var(--text-light);
        transition: var(--transition);
        flex-shrink: 0;
    }
    .faq-item.active .faq-question i { transform: rotate(180deg); color: var(--secondary); }
    .faq-item .faq-answer {
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.35s ease, padding 0.35s ease;
        padding: 0 24px;
        color: var(--text-light);
        line-height: 1.7;
        font-size: 15px;
    }
    .faq-item.active .faq-answer {
        max-height: 400px;
        padding: 0 24px 20px;
    }

    /* ===== CTA Section ===== */
    .cta-section {
        position: relative;
        padding: 80px 0;
        background: var(--primary-dark);
        overflow: hidden;
    }
    .cta-section::before {
        content: '';
        position: absolute;
        inset: 0;
        background: url('/assets/images/backpic/back-2.webp') center center / cover no-repeat;
        opacity: 0.15;
        z-index: 0;
    }
    .cta-section::after {
        content: '';
        position: absolute;
        inset: 0;
        background: linear-gradient(135deg, rgba(15,36,64,0.95) 0%, rgba(30,58,95,0.85) 100%);
        z-index: 1;
    }
    .cta-section .container { position: relative; z-index: 2; text-align: center; }
    .cta-section h2 {
        font-size: 38px;
        font-weight: 800;
        color: #fff;
        margin-bottom: 16px;
    }
    .cta-section h2 span { color: var(--accent); }
    .cta-section p {
        font-size: 18px;
        color: rgba(255,255,255,0.7);
        max-width: 560px;
        margin: 0 auto 32px;
        line-height: 1.7;
    }
    .cta-section .cta-actions {
        display: flex;
        flex-wrap: wrap;
        gap: 16px;
        justify-content: center;
    }

    /* ===== Footer ===== */
    .site-footer {
        background: var(--primary-dark);
        color: rgba(255,255,255,0.6);
        padding: 40px 0 28px;
        border-top: 1px solid rgba(255,255,255,0.06);
    }
    .site-footer .footer-grid {
        display: grid;
        grid-template-columns: 2fr 1fr 1fr;
        gap: 40px;
        margin-bottom: 32px;
    }
    .site-footer .footer-brand .brand-text {
        font-size: 20px;
        font-weight: 700;
        color: #fff;
        margin-bottom: 12px;
    }
    .site-footer .footer-brand .brand-text span { color: var(--accent); }
    .site-footer .footer-brand p { font-size: 14px; line-height: 1.7; max-width: 320px; }
    .site-footer h4 {
        font-size: 15px;
        font-weight: 700;
        color: #fff;
        margin-bottom: 16px;
    }
    .site-footer .footer-links { display: flex; flex-direction: column; gap: 8px; }
    .site-footer .footer-links a {
        font-size: 14px;
        color: rgba(255,255,255,0.5);
        transition: var(--transition);
    }
    .site-footer .footer-links a:hover { color: var(--accent); padding-left: 4px; }
    .site-footer .footer-bottom {
        border-top: 1px solid rgba(255,255,255,0.06);
        padding-top: 20px;
        display: flex;
        justify-content: space-between;
        align-items: center;
        flex-wrap: wrap;
        gap: 12px;
        font-size: 13px;
    }
    .site-footer .footer-bottom a { color: rgba(255,255,255,0.5); }
    .site-footer .footer-bottom a:hover { color: var(--accent); }

    /* ===== Responsive ===== */
    @media (max-width: 1024px) {
        .hero .hero-grid { grid-template-columns: 1fr; gap: 40px; }
        .hero .hero-stats { max-width: 480px; }
        .features-grid { grid-template-columns: repeat(2, 1fr); }
        .cover-cards { grid-template-columns: 1fr; }
        .trust-grid { grid-template-columns: repeat(2, 1fr); }
        .site-footer .footer-grid { grid-template-columns: 1fr 1fr; }
    }

    @media (max-width: 768px) {
        :root { --nav-width: 0px; }
        .side-nav {
            transform: translateX(-100%);
            width: 280px;
        }
        .side-nav.open { transform: translateX(0); }
        .main-content { margin-left: 0; }
        .mobile-header { display: flex; }
        .nav-overlay.show { display: block; }
        .hero { padding: 60px 0 50px; min-height: auto; }
        .hero h1 { font-size: 32px; }
        .hero .hero-sub { font-size: 16px; }
        .hero .hero-stats { grid-template-columns: repeat(3, 1fr); padding: 20px; gap: 12px; }
        .hero .hero-stats .stat-number { font-size: 28px; }
        .section { padding: 60px 0; }
        .section-header h2 { font-size: 28px; }
        .features-grid { grid-template-columns: 1fr; gap: 20px; }
        .cover-cards { gap: 20px; }
        .content-item { flex-wrap: wrap; gap: 12px; padding: 16px; }
        .content-item .item-index { width: 32px; height: 32px; font-size: 14px; }
        .trust-grid { grid-template-columns: repeat(2, 1fr); gap: 16px; }
        .cta-section h2 { font-size: 28px; }
        .cta-section p { font-size: 16px; }
        .site-footer .footer-grid { grid-template-columns: 1fr; gap: 24px; }
        .site-footer .footer-bottom { flex-direction: column; text-align: center; }
    }

    @media (max-width: 520px) {
        .hero h1 { font-size: 26px; }
        .hero .hero-actions { flex-direction: column; width: 100%; }
        .hero .hero-actions .btn { width: 100%; }
        .hero .hero-stats { grid-template-columns: 1fr; gap: 16px; }
        .section-header h2 { font-size: 24px; }
        .trust-grid { grid-template-columns: 1fr; }
        .cover-card .card-img { height: 180px; }
        .faq-item .faq-question { font-size: 15px; padding: 16px 18px; }
        .faq-item .faq-answer { font-size: 14px; }
        .btn-lg { padding: 14px 28px; font-size: 15px; }
    }

    /* ===== Accessibility ===== */
    @media (prefers-reduced-motion: reduce) {
        *, *::before, *::after { transition: none !important; animation: none !important; }
    }

    /* ===== Scrollbar ===== */
    .side-nav::-webkit-scrollbar { width: 4px; }
    .side-nav::-webkit-scrollbar-track { background: transparent; }
    .side-nav::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.15); border-radius: 4px; }

/* roulang page: category1 */
/* ===== 设计变量 ===== */
        :root {
            --primary: #2563eb;
            --primary-dark: #1d4ed8;
            --primary-light: #3b82f6;
            --primary-bg: rgba(37, 99, 235, 0.06);
            --secondary: #0f172a;
            --secondary-light: #1e293b;
            --accent: #f59e0b;
            --accent-light: #fbbf24;
            --bg-body: #f8fafc;
            --bg-white: #ffffff;
            --bg-card: #ffffff;
            --bg-dark: #0f172a;
            --bg-dark-card: #1e293b;
            --text-primary: #0f172a;
            --text-secondary: #475569;
            --text-muted: #94a3b8;
            --text-inverse: #f1f5f9;
            --border-color: #e2e8f0;
            --border-light: #f1f5f9;
            --shadow-sm: 0 1px 3px rgba(15, 23, 42, 0.06);
            --shadow-md: 0 4px 16px rgba(15, 23, 42, 0.08);
            --shadow-lg: 0 12px 40px rgba(15, 23, 42, 0.1);
            --shadow-hover: 0 20px 48px rgba(15, 23, 42, 0.14);
            --radius-sm: 8px;
            --radius-md: 12px;
            --radius-lg: 20px;
            --radius-xl: 28px;
            --transition: all 0.3s cubic-bezier(.4,0,.2,1);
            --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, 'Noto Sans SC', sans-serif;
            --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
            --sidebar-width: 240px;
            --header-height: 0px;
            --max-width: 1200px;
            --gap: 32px;
            --gap-sm: 20px;
        }

        /* ===== Reset & Base ===== */
        *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
        html { font-size: 16px; scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }
        body {
            font-family: var(--font-sans);
            background: var(--bg-body);
            color: var(--text-primary);
            line-height: 1.7;
            display: flex;
            min-height: 100vh;
        }
        a { color: var(--primary); text-decoration: none; transition: var(--transition); }
        a:hover { color: var(--primary-dark); }
        img { max-width: 100%; height: auto; display: block; }
        ul, ol { list-style: none; }
        button, input, textarea { font-family: inherit; font-size: inherit; outline: none; border: none; }
        button { cursor: pointer; background: none; }
        h1, h2, h3, h4, h5, h6 { line-height: 1.3; font-weight: 700; color: var(--text-primary); }
        h1 { font-size: 2.75rem; letter-spacing: -0.02em; }
        h2 { font-size: 2rem; letter-spacing: -0.01em; }
        h3 { font-size: 1.375rem; }
        h4 { font-size: 1.125rem; }
        p { margin-bottom: 1rem; color: var(--text-secondary); }
        ::selection { background: var(--primary); color: #fff; }

        /* ===== Container ===== */
        .container {
            max-width: var(--max-width);
            margin: 0 auto;
            padding: 0 var(--gap);
        }

        /* ===== 侧边导航 ===== */
        .side-nav {
            position: fixed;
            top: 0; left: 0;
            width: var(--sidebar-width);
            height: 100vh;
            background: var(--bg-white);
            border-right: 1px solid var(--border-color);
            display: flex;
            flex-direction: column;
            z-index: 1000;
            padding: 24px 16px;
            transition: var(--transition);
        }
        .nav-brand {
            display: flex;
            align-items: center;
            gap: 12px;
            padding-bottom: 28px;
            border-bottom: 1px solid var(--border-color);
            margin-bottom: 20px;
        }
        .brand-icon {
            width: 40px; height: 40px;
            background: var(--primary);
            border-radius: var(--radius-sm);
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 800;
            font-size: 1.1rem;
            color: #fff;
            flex-shrink: 0;
            letter-spacing: -0.03em;
        }
        .brand-text {
            font-size: 1.2rem;
            font-weight: 700;
            color: var(--text-primary);
            line-height: 1.2;
        }
        .brand-text span { color: var(--primary); }
        .nav-items {
            display: flex;
            flex-direction: column;
            gap: 4px;
            flex: 1;
            overflow-y: auto;
        }
        .nav-item {
            display: flex;
            align-items: center;
            gap: 12px;
            padding: 12px 14px;
            border-radius: var(--radius-sm);
            color: var(--text-secondary);
            font-weight: 500;
            font-size: 0.95rem;
            transition: var(--transition);
        }
        .nav-item i { width: 20px; font-size: 1rem; color: var(--text-muted); transition: var(--transition); }
        .nav-item:hover { background: var(--primary-bg); color: var(--primary); }
        .nav-item:hover i { color: var(--primary); }
        .nav-item.active { background: var(--primary); color: #fff; }
        .nav-item.active i { color: #fff; }
        .nav-footer {
            padding-top: 16px;
            border-top: 1px solid var(--border-color);
            font-size: 0.75rem;
            color: var(--text-muted);
            text-align: center;
            line-height: 1.5;
        }

        /* ===== 主内容区 ===== */
        .main-content {
            margin-left: var(--sidebar-width);
            flex: 1;
            min-height: 100vh;
            display: flex;
            flex-direction: column;
        }

        /* ===== 移动端导航 ===== */
        .mobile-nav-toggle {
            display: none;
            position: fixed;
            top: 16px; left: 16px;
            z-index: 1100;
            width: 42px; height: 42px;
            background: var(--bg-white);
            border-radius: var(--radius-sm);
            box-shadow: var(--shadow-md);
            align-items: center;
            justify-content: center;
            font-size: 1.3rem;
            color: var(--text-primary);
            border: 1px solid var(--border-color);
            transition: var(--transition);
        }
        .mobile-nav-toggle:hover { background: var(--primary-bg); color: var(--primary); }

        /* ===== 页面顶部条 ===== */
        .page-topbar {
            display: none;
            position: fixed;
            top: 0; left: 0; right: 0;
            height: 64px;
            background: var(--bg-white);
            border-bottom: 1px solid var(--border-color);
            z-index: 1050;
            padding: 0 20px;
            align-items: center;
            gap: 16px;
        }
        .page-topbar .brand-text { font-size: 1rem; }

        /* ===== Hero ===== */
        .hero-section {
            padding: 80px 0 60px;
            background: linear-gradient(135deg, var(--bg-dark) 0%, var(--secondary-light) 100%);
            position: relative;
            overflow: hidden;
            min-height: 480px;
            display: flex;
            align-items: center;
        }
        .hero-section::before {
            content: '';
            position: absolute;
            inset: 0;
            background: url('/assets/images/backpic/back-1.png') center/cover no-repeat;
            opacity: 0.12;
            pointer-events: none;
        }
        .hero-section::after {
            content: '';
            position: absolute;
            top: -50%; right: -20%;
            width: 600px; height: 600px;
            background: radial-gradient(circle, rgba(37,99,235,0.15) 0%, transparent 70%);
            border-radius: 50%;
            pointer-events: none;
        }
        .hero-content { position: relative; z-index: 2; max-width: 720px; }
        .hero-badge {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 6px 18px;
            background: rgba(255,255,255,0.08);
            border: 1px solid rgba(255,255,255,0.12);
            border-radius: 50px;
            font-size: 0.8rem;
            color: var(--text-inverse);
            letter-spacing: 0.03em;
            margin-bottom: 24px;
            backdrop-filter: blur(4px);
        }
        .hero-badge i { color: var(--accent); font-size: 0.7rem; }
        .hero-section h1 {
            color: #fff;
            font-size: 3rem;
            line-height: 1.2;
            margin-bottom: 20px;
        }
        .hero-section h1 span { color: var(--primary-light); }
        .hero-sub {
            font-size: 1.15rem;
            color: rgba(255,255,255,0.75);
            max-width: 600px;
            margin-bottom: 32px;
            line-height: 1.7;
        }
        .hero-actions { display: flex; gap: 14px; flex-wrap: wrap; }
        .btn {
            display: inline-flex;
            align-items: center;
            gap: 10px;
            padding: 14px 32px;
            border-radius: var(--radius-sm);
            font-weight: 600;
            font-size: 0.95rem;
            transition: var(--transition);
            border: 2px solid transparent;
            line-height: 1.2;
        }
        .btn-primary { background: var(--primary); color: #fff; border-color: var(--primary); }
        .btn-primary:hover { background: var(--primary-dark); border-color: var(--primary-dark); color: #fff; transform: translateY(-2px); box-shadow: 0 8px 24px rgba(37,99,235,0.3); }
        .btn-outline-light { background: transparent; color: #fff; border-color: rgba(255,255,255,0.35); }
        .btn-outline-light:hover { background: rgba(255,255,255,0.1); border-color: rgba(255,255,255,0.6); color: #fff; transform: translateY(-2px); }
        .btn-accent { background: var(--accent); color: var(--secondary); border-color: var(--accent); }
        .btn-accent:hover { background: var(--accent-light); border-color: var(--accent-light); color: var(--secondary); transform: translateY(-2px); box-shadow: 0 8px 24px rgba(245,158,11,0.3); }

        /* ===== 统计条 ===== */
        .stats-bar {
            background: var(--bg-white);
            padding: 40px 0;
            border-bottom: 1px solid var(--border-color);
        }
        .stats-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: var(--gap);
        }
        .stat-item { text-align: center; }
        .stat-number {
            font-size: 2.4rem;
            font-weight: 800;
            color: var(--primary);
            line-height: 1.2;
            letter-spacing: -0.02em;
        }
        .stat-number span { font-size: 1.4rem; font-weight: 600; }
        .stat-label { font-size: 0.9rem; color: var(--text-secondary); margin-top: 6px; }

        /* ===== 板块通用 ===== */
        .section-block {
            padding: 72px 0;
        }
        .section-block.alt-bg { background: var(--primary-bg); }
        .section-block.dark-bg { background: var(--bg-dark); color: var(--text-inverse); }
        .section-block.dark-bg h2, .section-block.dark-bg h3, .section-block.dark-bg .section-subtitle { color: #fff; }
        .section-block.dark-bg p { color: rgba(255,255,255,0.7); }
        .section-title {
            text-align: center;
            margin-bottom: 12px;
        }
        .section-subtitle {
            text-align: center;
            font-size: 1.05rem;
            color: var(--text-secondary);
            max-width: 600px;
            margin: 0 auto 48px;
        }
        .section-subtitle.light { color: rgba(255,255,255,0.65); }

        /* ===== 卡片网格 ===== */
        .card-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: var(--gap);
        }
        .card-grid.cols-2 { grid-template-columns: repeat(2, 1fr); }
        .card-grid.cols-4 { grid-template-columns: repeat(4, 1fr); }
        .card {
            background: var(--bg-card);
            border-radius: var(--radius-md);
            padding: 32px 28px;
            box-shadow: var(--shadow-sm);
            border: 1px solid var(--border-color);
            transition: var(--transition);
        }
        .card:hover { box-shadow: var(--shadow-hover); transform: translateY(-4px); border-color: var(--primary-light); }
        .card-icon {
            width: 52px; height: 52px;
            background: var(--primary-bg);
            border-radius: var(--radius-sm);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.4rem;
            color: var(--primary);
            margin-bottom: 18px;
            transition: var(--transition);
        }
        .card:hover .card-icon { background: var(--primary); color: #fff; }
        .card h3 { margin-bottom: 10px; font-size: 1.15rem; }
        .card p { font-size: 0.92rem; color: var(--text-secondary); margin-bottom: 0; }
        .card .card-tag {
            display: inline-block;
            padding: 3px 12px;
            background: var(--primary-bg);
            color: var(--primary);
            border-radius: 50px;
            font-size: 0.75rem;
            font-weight: 600;
            margin-top: 14px;
        }

        /* ===== 图文交替 ===== */
        .alt-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 56px;
            align-items: center;
        }
        .alt-grid.reverse { direction: rtl; }
        .alt-grid.reverse > * { direction: ltr; }
        .alt-image {
            border-radius: var(--radius-lg);
            overflow: hidden;
            box-shadow: var(--shadow-lg);
            background: var(--border-color);
        }
        .alt-image img { width: 100%; height: 360px; object-fit: cover; }
        .alt-text h2 { margin-bottom: 16px; }
        .alt-text p { font-size: 1rem; line-height: 1.8; }
        .alt-list { margin-top: 20px; display: flex; flex-direction: column; gap: 12px; }
        .alt-list li {
            display: flex;
            align-items: flex-start;
            gap: 12px;
            font-size: 0.95rem;
            color: var(--text-secondary);
        }
        .alt-list li i { color: var(--primary); font-size: 1rem; margin-top: 4px; flex-shrink: 0; }

        /* ===== 流程步骤 ===== */
        .steps-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: var(--gap);
            counter-reset: step;
        }
        .step-card {
            background: var(--bg-card);
            border-radius: var(--radius-md);
            padding: 32px 24px;
            text-align: center;
            box-shadow: var(--shadow-sm);
            border: 1px solid var(--border-color);
            transition: var(--transition);
            position: relative;
        }
        .step-card:hover { box-shadow: var(--shadow-hover); transform: translateY(-4px); }
        .step-number {
            width: 48px; height: 48px;
            background: var(--primary);
            color: #fff;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 800;
            font-size: 1.2rem;
            margin: 0 auto 16px;
        }
        .step-card h4 { margin-bottom: 8px; font-size: 1.05rem; }
        .step-card p { font-size: 0.88rem; margin-bottom: 0; }

        /* ===== 场景 ===== */
        .scene-grid {
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: var(--gap);
        }
        .scene-card {
            background: var(--bg-white);
            border-radius: var(--radius-md);
            padding: 32px 28px;
            border: 1px solid var(--border-color);
            box-shadow: var(--shadow-sm);
            display: flex;
            gap: 20px;
            align-items: flex-start;
            transition: var(--transition);
        }
        .scene-card:hover { box-shadow: var(--shadow-hover); transform: translateY(-3px); border-color: var(--primary-light); }
        .scene-icon {
            width: 48px; height: 48px;
            background: var(--primary-bg);
            border-radius: var(--radius-sm);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.2rem;
            color: var(--primary);
            flex-shrink: 0;
        }
        .scene-card h4 { margin-bottom: 6px; font-size: 1.05rem; }
        .scene-card p { font-size: 0.9rem; margin-bottom: 0; }

        /* ===== 数据看板 ===== */
        .dashboard-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: var(--gap);
        }
        .dash-card {
            background: var(--bg-dark-card);
            border-radius: var(--radius-md);
            padding: 28px 24px;
            text-align: center;
            border: 1px solid rgba(255,255,255,0.06);
            transition: var(--transition);
        }
        .dash-card:hover { border-color: var(--primary-light); transform: translateY(-3px); }
        .dash-number {
            font-size: 2.6rem;
            font-weight: 800;
            color: var(--primary-light);
            line-height: 1.2;
            letter-spacing: -0.02em;
        }
        .dash-label { color: rgba(255,255,255,0.6); font-size: 0.85rem; margin-top: 6px; }

        /* ===== FAQ ===== */
        .faq-list {
            max-width: 760px;
            margin: 0 auto;
            display: flex;
            flex-direction: column;
            gap: 12px;
        }
        .faq-item {
            background: var(--bg-white);
            border-radius: var(--radius-md);
            border: 1px solid var(--border-color);
            overflow: hidden;
            transition: var(--transition);
        }
        .faq-item:hover { border-color: var(--primary-light); }
        .faq-question {
            padding: 20px 24px;
            font-weight: 600;
            font-size: 1rem;
            color: var(--text-primary);
            display: flex;
            justify-content: space-between;
            align-items: center;
            cursor: pointer;
            background: none;
            width: 100%;
            text-align: left;
            transition: var(--transition);
        }
        .faq-question i { color: var(--text-muted); transition: var(--transition); font-size: 0.85rem; }
        .faq-question.open i { transform: rotate(180deg); color: var(--primary); }
        .faq-answer {
            padding: 0 24px 20px;
            font-size: 0.92rem;
            color: var(--text-secondary);
            line-height: 1.7;
            display: none;
        }
        .faq-answer.show { display: block; }

        /* ===== CTA ===== */
        .cta-section {
            padding: 72px 0;
            background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 100%);
            text-align: center;
            position: relative;
            overflow: hidden;
        }
        .cta-section::before {
            content: '';
            position: absolute;
            inset: 0;
            background: url('/assets/images/backpic/back-3.webp') center/cover no-repeat;
            opacity: 0.08;
            pointer-events: none;
        }
        .cta-content { position: relative; z-index: 2; }
        .cta-content h2 { color: #fff; font-size: 2.2rem; margin-bottom: 12px; }
        .cta-content p { color: rgba(255,255,255,0.8); font-size: 1.05rem; max-width: 560px; margin: 0 auto 28px; }
        .cta-actions { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }

        /* ===== 页脚 ===== */
        .site-footer {
            background: var(--bg-dark);
            color: rgba(255,255,255,0.7);
            padding: 56px 0 32px;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr;
            gap: 48px;
            padding-bottom: 32px;
            border-bottom: 1px solid rgba(255,255,255,0.08);
        }
        .footer-brand .brand-text { font-size: 1.3rem; color: #fff; margin-bottom: 12px; }
        .footer-brand .brand-text span { color: var(--primary-light); }
        .footer-brand p { font-size: 0.88rem; color: rgba(255,255,255,0.55); max-width: 320px; line-height: 1.7; }
        .site-footer h4 { color: #fff; font-size: 0.95rem; margin-bottom: 16px; font-weight: 600; }
        .footer-links { display: flex; flex-direction: column; gap: 10px; }
        .footer-links a { color: rgba(255,255,255,0.55); font-size: 0.88rem; transition: var(--transition); }
        .footer-links a:hover { color: var(--primary-light); padding-left: 4px; }
        .footer-bottom {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding-top: 24px;
            font-size: 0.8rem;
            color: rgba(255,255,255,0.4);
        }
        .footer-bottom a { color: rgba(255,255,255,0.5); }
        .footer-bottom a:hover { color: var(--primary-light); }

        /* ===== 响应式 ===== */
        @media (max-width: 1024px) {
            :root { --sidebar-width: 200px; }
            .card-grid { grid-template-columns: repeat(2, 1fr); }
            .card-grid.cols-4 { grid-template-columns: repeat(2, 1fr); }
            .steps-grid { grid-template-columns: repeat(2, 1fr); }
            .dashboard-grid { grid-template-columns: repeat(2, 1fr); }
            .alt-grid { gap: 32px; }
            .hero-section h1 { font-size: 2.4rem; }
            .stat-number { font-size: 2rem; }
        }

        @media (max-width: 768px) {
            body { display: block; }
            .side-nav {
                transform: translateX(-100%);
                width: 280px;
                box-shadow: var(--shadow-lg);
            }
            .side-nav.open { transform: translateX(0); }
            .main-content { margin-left: 0; }
            .mobile-nav-toggle { display: flex; }
            .page-topbar { display: flex; }
            .main-content { padding-top: 64px; }
            .hero-section { padding: 60px 0 48px; min-height: auto; }
            .hero-section h1 { font-size: 2rem; }
            .hero-sub { font-size: 1rem; }
            .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 20px; }
            .stat-number { font-size: 1.8rem; }
            .card-grid { grid-template-columns: 1fr; }
            .card-grid.cols-2 { grid-template-columns: 1fr; }
            .card-grid.cols-4 { grid-template-columns: repeat(2, 1fr); }
            .alt-grid { grid-template-columns: 1fr; gap: 24px; }
            .alt-grid.reverse { direction: ltr; }
            .alt-image img { height: 240px; }
            .steps-grid { grid-template-columns: 1fr 1fr; }
            .scene-grid { grid-template-columns: 1fr; }
            .dashboard-grid { grid-template-columns: repeat(2, 1fr); }
            .footer-grid { grid-template-columns: 1fr; gap: 28px; }
            .footer-bottom { flex-direction: column; gap: 8px; text-align: center; }
            .section-block { padding: 48px 0; }
            .cta-content h2 { font-size: 1.6rem; }
            .hero-actions { flex-direction: column; align-items: flex-start; }
            .btn { width: 100%; justify-content: center; }
            .cta-actions { flex-direction: column; align-items: center; }
            .cta-actions .btn { max-width: 300px; }
            .stat-item { padding: 8px 0; }
        }

        @media (max-width: 520px) {
            .hero-section h1 { font-size: 1.6rem; }
            .hero-sub { font-size: 0.92rem; }
            .stats-grid { grid-template-columns: 1fr 1fr; gap: 16px; }
            .stat-number { font-size: 1.5rem; }
            .card-grid.cols-4 { grid-template-columns: 1fr; }
            .steps-grid { grid-template-columns: 1fr; }
            .dashboard-grid { grid-template-columns: 1fr; }
            .scene-card { flex-direction: column; padding: 24px 20px; }
            .faq-question { padding: 16px 18px; font-size: 0.92rem; }
            .faq-answer { padding: 0 18px 16px; font-size: 0.85rem; }
            .container { padding: 0 16px; }
            .section-block { padding: 36px 0; }
            .btn { padding: 12px 24px; font-size: 0.88rem; }
            .alt-image img { height: 180px; }
        }

        /* ===== 辅助 ===== */
        .text-center { text-align: center; }
        .mt-12 { margin-top: 12px; }
        .mt-24 { margin-top: 24px; }
        .gap-12 { gap: 12px; }
        .flex-center { display: flex; align-items: center; justify-content: center; }
        .badge {
            display: inline-block;
            padding: 4px 14px;
            border-radius: 50px;
            font-size: 0.75rem;
            font-weight: 600;
            background: var(--primary-bg);
            color: var(--primary);
        }
        .badge-accent { background: rgba(245,158,11,0.12); color: var(--accent); }

/* roulang page: article */
/* ===== 设计变量 ===== */
        :root {
            --nav-bg: #0f0e17;
            --nav-text: #ffffff;
            --nav-hover: #ff6b35;
            --nav-active-bg: rgba(255, 107, 53, 0.15);
            --primary: #ff6b35;
            --primary-hover: #e85d2a;
            --primary-light: rgba(255, 107, 53, 0.08);
            --primary-gradient: linear-gradient(135deg, #ff6b35 0%, #f7934b 100%);
            --bg-body: #f8f9fa;
            --bg-white: #ffffff;
            --text-dark: #1a1a2e;
            --text-muted: #6b7280;
            --text-light: #9ca3af;
            --border-color: #e5e7eb;
            --radius-sm: 8px;
            --radius-md: 12px;
            --radius-lg: 20px;
            --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.04);
            --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.06);
            --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.08);
            --shadow-hover: 0 16px 48px rgba(0, 0, 0, 0.12);
            --transition: 0.3s ease;
            --nav-width: 240px;
            --max-width: 1200px;
            --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
        }

        /* ===== 基础 Reset ===== */
        *,
        *::before,
        *::after {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }
        html {
            scroll-behavior: smooth;
            -webkit-font-smoothing: antialiased;
        }
        body {
            font-family: var(--font-sans);
            font-size: 16px;
            line-height: 1.7;
            color: var(--text-dark);
            background: var(--bg-body);
            display: flex;
            min-height: 100vh;
        }
        a {
            color: inherit;
            text-decoration: none;
            transition: var(--transition);
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
            border-radius: var(--radius-sm);
        }
        button,
        input,
        textarea {
            font-family: inherit;
            font-size: inherit;
            border: none;
            outline: none;
            transition: var(--transition);
        }
        ul,
        ol {
            list-style: none;
        }
        h1,
        h2,
        h3,
        h4,
        h5,
        h6 {
            line-height: 1.3;
            font-weight: 700;
            color: var(--text-dark);
        }
        h1 {
            font-size: 2.4rem;
        }
        h2 {
            font-size: 1.8rem;
            margin-bottom: 0.5rem;
        }
        h3 {
            font-size: 1.3rem;
        }
        p {
            margin-bottom: 1rem;
            color: var(--text-muted);
        }
        .container {
            width: 100%;
            max-width: var(--max-width);
            margin: 0 auto;
            padding: 0 24px;
        }

        /* ===== 左侧导航 ===== */
        .side-nav {
            position: fixed;
            top: 0;
            left: 0;
            width: var(--nav-width);
            height: 100vh;
            background: var(--nav-bg);
            color: var(--nav-text);
            display: flex;
            flex-direction: column;
            z-index: 1000;
            padding: 28px 20px 20px;
            overflow-y: auto;
            transition: transform var(--transition);
        }
        .nav-brand {
            display: flex;
            align-items: center;
            gap: 12px;
            padding-bottom: 32px;
            border-bottom: 1px solid rgba(255, 255, 255, 0.06);
            margin-bottom: 28px;
        }
        .brand-icon {
            width: 44px;
            height: 44px;
            background: var(--primary-gradient);
            border-radius: var(--radius-sm);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.1rem;
            font-weight: 800;
            color: #fff;
            letter-spacing: 0.5px;
            flex-shrink: 0;
        }
        .brand-text {
            font-size: 1.25rem;
            font-weight: 700;
            letter-spacing: 0.3px;
        }
        .brand-text span {
            color: var(--primary);
        }
        .nav-items {
            flex: 1;
            display: flex;
            flex-direction: column;
            gap: 4px;
        }
        .nav-item {
            display: flex;
            align-items: center;
            gap: 14px;
            padding: 12px 16px;
            border-radius: var(--radius-sm);
            font-size: 0.95rem;
            font-weight: 500;
            color: rgba(255, 255, 255, 0.75);
            transition: var(--transition);
        }
        .nav-item i {
            width: 20px;
            text-align: center;
            font-size: 1.05rem;
            color: rgba(255, 255, 255, 0.5);
            transition: var(--transition);
        }
        .nav-item:hover {
            background: rgba(255, 255, 255, 0.06);
            color: #fff;
        }
        .nav-item:hover i {
            color: var(--primary);
        }
        .nav-item.active {
            background: var(--nav-active-bg);
            color: var(--primary);
        }
        .nav-item.active i {
            color: var(--primary);
        }
        .nav-footer {
            padding-top: 20px;
            border-top: 1px solid rgba(255, 255, 255, 0.06);
            font-size: 0.75rem;
            color: rgba(255, 255, 255, 0.35);
            text-align: center;
            line-height: 1.6;
        }
        .mobile-menu-toggle {
            display: none;
            position: fixed;
            top: 16px;
            left: 16px;
            z-index: 1100;
            width: 42px;
            height: 42px;
            background: var(--primary);
            color: #fff;
            border-radius: var(--radius-sm);
            align-items: center;
            justify-content: center;
            font-size: 1.3rem;
            cursor: pointer;
            box-shadow: var(--shadow-md);
            border: none;
        }
        .mobile-overlay {
            display: none;
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: rgba(0, 0, 0, 0.5);
            z-index: 999;
        }

        /* ===== 主内容区 ===== */
        .main-content {
            margin-left: var(--nav-width);
            flex: 1;
            min-height: 100vh;
            display: flex;
            flex-direction: column;
        }

        /* ===== 文章头部 ===== */
        .article-header {
            background: linear-gradient(135deg, #0f0e17 0%, #1a1a2e 100%);
            padding: 80px 0 60px;
            position: relative;
            overflow: hidden;
            min-height: 320px;
            display: flex;
            align-items: center;
        }
        .article-header::before {
            content: '';
            position: absolute;
            inset: 0;
            background: url('/assets/images/backpic/back-1.png') center/cover no-repeat;
            opacity: 0.12;
            mix-blend-mode: overlay;
        }
        .article-header .container {
            position: relative;
            z-index: 2;
        }
        .article-breadcrumb {
            display: flex;
            align-items: center;
            gap: 8px;
            font-size: 0.85rem;
            color: rgba(255, 255, 255, 0.5);
            margin-bottom: 20px;
            flex-wrap: wrap;
        }
        .article-breadcrumb a {
            color: rgba(255, 255, 255, 0.6);
            transition: var(--transition);
        }
        .article-breadcrumb a:hover {
            color: var(--primary);
        }
        .article-breadcrumb .sep {
            color: rgba(255, 255, 255, 0.25);
        }
        .article-breadcrumb .current {
            color: rgba(255, 255, 255, 0.85);
        }
        .article-meta-top {
            display: flex;
            align-items: center;
            gap: 20px;
            flex-wrap: wrap;
            margin-bottom: 16px;
        }
        .article-meta-top .cat-badge {
            background: var(--primary);
            color: #fff;
            font-size: 0.75rem;
            font-weight: 600;
            padding: 4px 14px;
            border-radius: 20px;
            letter-spacing: 0.3px;
        }
        .article-meta-top .date {
            font-size: 0.85rem;
            color: rgba(255, 255, 255, 0.55);
            display: flex;
            align-items: center;
            gap: 6px;
        }
        .article-meta-top .date i {
            font-size: 0.8rem;
        }
        .article-header h1 {
            color: #fff;
            font-size: 2.6rem;
            font-weight: 800;
            line-height: 1.25;
            max-width: 860px;
            letter-spacing: -0.3px;
            margin-bottom: 0;
        }
        .article-header .header-desc {
            color: rgba(255, 255, 255, 0.6);
            font-size: 1.05rem;
            margin-top: 16px;
            max-width: 700px;
            line-height: 1.6;
        }

        /* ===== 文章正文 ===== */
        .article-body-wrap {
            padding: 60px 0 40px;
            background: var(--bg-white);
        }
        .article-body {
            max-width: 820px;
            margin: 0 auto;
            font-size: 1.05rem;
            line-height: 1.9;
            color: var(--text-dark);
        }
        .article-body h2,
        .article-body h3,
        .article-body h4 {
            margin-top: 2rem;
            margin-bottom: 0.8rem;
            color: var(--text-dark);
        }
        .article-body h2 {
            font-size: 1.6rem;
            border-bottom: 2px solid var(--border-color);
            padding-bottom: 0.4rem;
        }
        .article-body h3 {
            font-size: 1.25rem;
        }
        .article-body p {
            margin-bottom: 1.2rem;
            color: #374151;
        }
        .article-body ul,
        .article-body ol {
            margin-bottom: 1.2rem;
            padding-left: 1.6rem;
            color: #374151;
        }
        .article-body ul li {
            list-style: disc;
            margin-bottom: 0.3rem;
        }
        .article-body ol li {
            list-style: decimal;
            margin-bottom: 0.3rem;
        }
        .article-body blockquote {
            border-left: 4px solid var(--primary);
            background: var(--primary-light);
            padding: 16px 24px;
            margin: 1.6rem 0;
            border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
            color: #374151;
            font-style: italic;
        }
        .article-body a {
            color: var(--primary);
            text-decoration: underline;
            text-underline-offset: 2px;
        }
        .article-body a:hover {
            color: var(--primary-hover);
        }
        .article-body img {
            border-radius: var(--radius-md);
            margin: 1.6rem 0;
            box-shadow: var(--shadow-md);
        }
        .article-body code {
            background: #f1f5f9;
            padding: 2px 8px;
            border-radius: 4px;
            font-size: 0.9em;
            color: #e11d48;
        }
        .article-body pre {
            background: #1e293b;
            color: #e2e8f0;
            padding: 20px 24px;
            border-radius: var(--radius-md);
            overflow-x: auto;
            margin: 1.6rem 0;
            font-size: 0.9rem;
            line-height: 1.6;
        }
        .article-body pre code {
            background: none;
            color: inherit;
            padding: 0;
        }
        .article-not-found {
            text-align: center;
            padding: 80px 20px;
        }
        .article-not-found i {
            font-size: 3rem;
            color: var(--text-light);
            margin-bottom: 20px;
        }
        .article-not-found h2 {
            font-size: 1.8rem;
            margin-bottom: 12px;
        }
        .article-not-found p {
            color: var(--text-muted);
            margin-bottom: 24px;
        }
        .article-not-found .btn-back {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            background: var(--primary);
            color: #fff;
            padding: 12px 32px;
            border-radius: var(--radius-sm);
            font-weight: 600;
            transition: var(--transition);
        }
        .article-not-found .btn-back:hover {
            background: var(--primary-hover);
            transform: translateY(-2px);
            box-shadow: var(--shadow-md);
        }

        /* ===== 文章底部信息 ===== */
        .article-footer-meta {
            max-width: 820px;
            margin: 0 auto;
            padding: 32px 0 0;
            border-top: 1px solid var(--border-color);
            display: flex;
            align-items: center;
            justify-content: space-between;
            flex-wrap: wrap;
            gap: 16px;
        }
        .article-tags {
            display: flex;
            align-items: center;
            gap: 10px;
            flex-wrap: wrap;
        }
        .article-tags span {
            font-size: 0.85rem;
            color: var(--text-muted);
            font-weight: 600;
        }
        .article-tags .tag {
            background: var(--primary-light);
            color: var(--primary);
            font-size: 0.8rem;
            font-weight: 500;
            padding: 4px 14px;
            border-radius: 20px;
            transition: var(--transition);
        }
        .article-tags .tag:hover {
            background: var(--primary);
            color: #fff;
        }
        .article-share {
            display: flex;
            align-items: center;
            gap: 10px;
        }
        .article-share span {
            font-size: 0.85rem;
            color: var(--text-muted);
        }
        .article-share a {
            width: 36px;
            height: 36px;
            border-radius: 50%;
            background: var(--bg-body);
            display: flex;
            align-items: center;
            justify-content: center;
            color: var(--text-muted);
            transition: var(--transition);
            font-size: 0.95rem;
        }
        .article-share a:hover {
            background: var(--primary);
            color: #fff;
            transform: translateY(-2px);
        }

        /* ===== 相关推荐 ===== */
        .related-section {
            padding: 60px 0;
            background: var(--bg-body);
        }
        .related-section .section-title {
            text-align: center;
            margin-bottom: 40px;
        }
        .related-section .section-title h2 {
            font-size: 1.8rem;
            font-weight: 700;
        }
        .related-section .section-title p {
            color: var(--text-muted);
            max-width: 540px;
            margin: 8px auto 0;
        }
        .related-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 28px;
        }
        .related-card {
            background: var(--bg-white);
            border-radius: var(--radius-md);
            overflow: hidden;
            box-shadow: var(--shadow-sm);
            transition: var(--transition);
            border: 1px solid var(--border-color);
        }
        .related-card:hover {
            transform: translateY(-6px);
            box-shadow: var(--shadow-hover);
            border-color: transparent;
        }
        .related-card .card-img {
            width: 100%;
            height: 200px;
            object-fit: cover;
            border-radius: 0;
        }
        .related-card .card-body {
            padding: 20px 22px 24px;
        }
        .related-card .card-body h3 {
            font-size: 1.1rem;
            font-weight: 700;
            margin-bottom: 8px;
            line-height: 1.4;
        }
        .related-card .card-body h3 a {
            color: var(--text-dark);
        }
        .related-card .card-body h3 a:hover {
            color: var(--primary);
        }
        .related-card .card-body p {
            font-size: 0.9rem;
            color: var(--text-muted);
            margin-bottom: 12px;
            line-height: 1.6;
        }
        .related-card .card-body .read-more {
            font-size: 0.85rem;
            font-weight: 600;
            color: var(--primary);
            display: inline-flex;
            align-items: center;
            gap: 6px;
        }
        .related-card .card-body .read-more i {
            font-size: 0.75rem;
            transition: var(--transition);
        }
        .related-card .card-body .read-more:hover i {
            transform: translateX(4px);
        }

        /* ===== FAQ 板块 ===== */
        .faq-section {
            padding: 60px 0;
            background: var(--bg-white);
        }
        .faq-section .section-title {
            text-align: center;
            margin-bottom: 40px;
        }
        .faq-section .section-title h2 {
            font-size: 1.8rem;
            font-weight: 700;
        }
        .faq-section .section-title p {
            color: var(--text-muted);
            max-width: 540px;
            margin: 8px auto 0;
        }
        .faq-list {
            max-width: 820px;
            margin: 0 auto;
            display: flex;
            flex-direction: column;
            gap: 12px;
        }
        .faq-item {
            border: 1px solid var(--border-color);
            border-radius: var(--radius-md);
            overflow: hidden;
            transition: var(--transition);
            background: var(--bg-white);
        }
        .faq-item:hover {
            border-color: var(--primary);
            box-shadow: var(--shadow-sm);
        }
        .faq-question {
            padding: 18px 24px;
            display: flex;
            align-items: center;
            justify-content: space-between;
            cursor: pointer;
            font-weight: 600;
            font-size: 1.02rem;
            color: var(--text-dark);
            background: none;
            width: 100%;
            text-align: left;
            gap: 16px;
            transition: var(--transition);
        }
        .faq-question:hover {
            color: var(--primary);
        }
        .faq-question .faq-icon {
            flex-shrink: 0;
            width: 28px;
            height: 28px;
            border-radius: 50%;
            background: var(--primary-light);
            color: var(--primary);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 0.8rem;
            transition: var(--transition);
        }
        .faq-item.active .faq-icon {
            background: var(--primary);
            color: #fff;
            transform: rotate(180deg);
        }
        .faq-answer {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.35s ease, padding 0.35s ease;
            padding: 0 24px;
            color: var(--text-muted);
            font-size: 0.95rem;
            line-height: 1.7;
        }
        .faq-item.active .faq-answer {
            max-height: 300px;
            padding: 0 24px 20px;
        }

        /* ===== CTA 板块 ===== */
        .cta-section {
            padding: 80px 0;
            background: linear-gradient(135deg, #0f0e17 0%, #1a1a2e 100%);
            text-align: center;
            position: relative;
            overflow: hidden;
        }
        .cta-section::before {
            content: '';
            position: absolute;
            inset: 0;
            background: url('/assets/images/backpic/back-2.webp') center/cover no-repeat;
            opacity: 0.08;
            mix-blend-mode: overlay;
        }
        .cta-section .container {
            position: relative;
            z-index: 2;
        }
        .cta-section h2 {
            color: #fff;
            font-size: 2rem;
            font-weight: 800;
            margin-bottom: 12px;
        }
        .cta-section p {
            color: rgba(255, 255, 255, 0.65);
            font-size: 1.1rem;
            max-width: 600px;
            margin: 0 auto 32px;
            line-height: 1.6;
        }
        .cta-buttons {
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 16px;
            flex-wrap: wrap;
        }
        .btn-primary {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            background: var(--primary-gradient);
            color: #fff;
            padding: 14px 36px;
            border-radius: var(--radius-sm);
            font-weight: 700;
            font-size: 1rem;
            transition: var(--transition);
            box-shadow: 0 4px 20px rgba(255, 107, 53, 0.35);
            border: none;
            cursor: pointer;
        }
        .btn-primary:hover {
            transform: translateY(-3px);
            box-shadow: 0 8px 32px rgba(255, 107, 53, 0.45);
            color: #fff;
        }
        .btn-secondary {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            background: transparent;
            color: #fff;
            padding: 14px 36px;
            border-radius: var(--radius-sm);
            font-weight: 600;
            font-size: 1rem;
            border: 2px solid rgba(255, 255, 255, 0.2);
            transition: var(--transition);
            cursor: pointer;
        }
        .btn-secondary:hover {
            border-color: var(--primary);
            color: var(--primary);
            transform: translateY(-3px);
            background: rgba(255, 107, 53, 0.06);
        }

        /* ===== 页脚 ===== */
        .site-footer {
            background: #0a0a12;
            color: rgba(255, 255, 255, 0.75);
            padding: 56px 0 32px;
        }
        .site-footer .footer-grid {
            display: grid;
            grid-template-columns: 1.8fr 1fr 1fr;
            gap: 40px;
            padding-bottom: 32px;
            border-bottom: 1px solid rgba(255, 255, 255, 0.06);
        }
        .site-footer .footer-brand .brand-text {
            font-size: 1.3rem;
            color: #fff;
            margin-bottom: 12px;
        }
        .site-footer .footer-brand .brand-text span {
            color: var(--primary);
        }
        .site-footer .footer-brand p {
            font-size: 0.9rem;
            color: rgba(255, 255, 255, 0.5);
            line-height: 1.7;
            max-width: 360px;
        }
        .site-footer h4 {
            color: #fff;
            font-size: 0.95rem;
            font-weight: 700;
            margin-bottom: 16px;
            letter-spacing: 0.5px;
        }
        .site-footer .footer-links {
            display: flex;
            flex-direction: column;
            gap: 10px;
        }
        .site-footer .footer-links a {
            font-size: 0.88rem;
            color: rgba(255, 255, 255, 0.5);
            transition: var(--transition);
        }
        .site-footer .footer-links a:hover {
            color: var(--primary);
            padding-left: 4px;
        }
        .site-footer .footer-bottom {
            display: flex;
            align-items: center;
            justify-content: space-between;
            flex-wrap: wrap;
            gap: 12px;
            padding-top: 24px;
            font-size: 0.82rem;
            color: rgba(255, 255, 255, 0.3);
        }
        .site-footer .footer-bottom a {
            color: rgba(255, 255, 255, 0.4);
        }
        .site-footer .footer-bottom a:hover {
            color: var(--primary);
        }

        /* ===== 响应式 ===== */
        @media (max-width: 1024px) {
            .related-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .article-header h1 {
                font-size: 2.1rem;
            }
        }

        @media (max-width: 820px) {
            .site-footer .footer-grid {
                grid-template-columns: 1fr 1fr;
                gap: 32px;
            }
            .site-footer .footer-brand {
                grid-column: span 2;
            }
        }

        @media (max-width: 768px) {
            :root {
                --nav-width: 0px;
            }
            .side-nav {
                transform: translateX(-100%);
                width: 270px;
            }
            .side-nav.open {
                transform: translateX(0);
            }
            .mobile-menu-toggle {
                display: flex;
            }
            .mobile-overlay.active {
                display: block;
            }
            .main-content {
                margin-left: 0;
            }
            .article-header {
                padding: 100px 0 50px;
                min-height: 240px;
            }
            .article-header h1 {
                font-size: 1.7rem;
            }
            .article-body {
                padding: 0 16px;
                font-size: 1rem;
            }
            .related-grid {
                grid-template-columns: 1fr;
                gap: 20px;
            }
            .article-footer-meta {
                flex-direction: column;
                align-items: flex-start;
                gap: 12px;
            }
            .cta-section h2 {
                font-size: 1.5rem;
            }
            .cta-section p {
                font-size: 0.95rem;
            }
            .btn-primary,
            .btn-secondary {
                padding: 12px 28px;
                font-size: 0.95rem;
            }
            .site-footer .footer-grid {
                grid-template-columns: 1fr;
                gap: 28px;
            }
            .site-footer .footer-brand {
                grid-column: span 1;
            }
            .site-footer .footer-bottom {
                flex-direction: column;
                text-align: center;
            }
            .faq-question {
                font-size: 0.95rem;
                padding: 16px 18px;
            }
            .faq-answer {
                font-size: 0.9rem;
                padding: 0 18px;
            }
            .faq-item.active .faq-answer {
                padding: 0 18px 16px;
            }
        }

        @media (max-width: 520px) {
            .article-header h1 {
                font-size: 1.4rem;
            }
            .article-meta-top {
                gap: 12px;
            }
            .article-meta-top .cat-badge {
                font-size: 0.7rem;
                padding: 3px 12px;
            }
            .article-body h2 {
                font-size: 1.3rem;
            }
            .article-body h3 {
                font-size: 1.1rem;
            }
            .cta-buttons {
                flex-direction: column;
                gap: 12px;
            }
            .btn-primary,
            .btn-secondary {
                width: 100%;
                justify-content: center;
            }
            .related-card .card-img {
                height: 160px;
            }
            .brand-text {
                font-size: 1.1rem;
            }
        }

        /* ===== 滚动条美化 ===== */
        .main-content::-webkit-scrollbar {
            width: 6px;
        }
        .main-content::-webkit-scrollbar-track {
            background: transparent;
        }
        .main-content::-webkit-scrollbar-thumb {
            background: var(--border-color);
            border-radius: 3px;
        }
        .main-content::-webkit-scrollbar-thumb:hover {
            background: var(--text-light);
        }
        .side-nav::-webkit-scrollbar {
            width: 4px;
        }
        .side-nav::-webkit-scrollbar-track {
            background: transparent;
        }
        .side-nav::-webkit-scrollbar-thumb {
            background: rgba(255, 255, 255, 0.1);
            border-radius: 2px;
        }