/* roulang page: index */
:root {
            --brand: #2563EB;
            --brand-dark: #1D4ED8;
            --accent: #D97706;
            --canvas: #F8FAFC;
            --ink: #1E293B;
            --ink-soft: #64748B;
            --ink-light: #94A3B8;
            --line: #E2E8F0;
            --navbg: #EFF6FF;
            --footerbg: #0F1E3C;
        }

        * {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }

        html {
            scroll-behavior: smooth;
        }

        body {
            font-family: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans CJK SC', system-ui, sans-serif;
            background: var(--canvas);
            color: var(--ink);
            line-height: 1.6;
            -webkit-font-smoothing: antialiased;
        }

        a {
            text-decoration: none;
            color: inherit;
        }

        img {
            max-width: 100%;
            display: block;
        }

        button {
            cursor: pointer;
            font-family: inherit;
            border: none;
            background: none;
        }

        input,
        select,
        textarea {
            font-family: inherit;
            font-size: 14px;
            color: var(--ink);
        }

        /* 容器 */
        .container-x {
            max-width: 1280px;
            margin: 0 auto;
            padding-left: 16px;
            padding-right: 16px;
        }

        @media (min-width: 768px) {
            .container-x {
                padding-left: 24px;
                padding-right: 24px;
            }
        }

        /* 导航 */
        .nav-card {
            background: var(--navbg);
            box-shadow: 0 4px 20px rgba(30, 64, 175, 0.07);
            border-radius: 16px;
        }

        .nav-link {
            background: #fff;
            border: 1px solid var(--line);
            border-radius: 12px;
            padding: 8px 16px;
            font-size: 14px;
            font-weight: 500;
            color: var(--ink-soft);
            transition: all 0.2s ease;
            display: inline-flex;
            align-items: center;
            gap: 6px;
        }

        .nav-link:hover {
            background: #DBEAFE;
            border-color: var(--brand);
            color: var(--brand);
        }

        .nav-link.active {
            background: #DBEAFE;
            border-color: var(--brand);
            color: var(--brand);
            font-weight: 600;
        }

        /* 按钮 */
        .btn-primary {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            background: var(--brand);
            color: #fff;
            border-radius: 12px;
            padding: 10px 22px;
            font-size: 15px;
            font-weight: 600;
            transition: all 0.2s ease;
            border: 1px solid transparent;
        }

        .btn-primary:hover {
            background: var(--brand-dark);
            transform: translateY(-2px);
            box-shadow: 0 8px 24px rgba(37, 99, 235, 0.28);
        }

        .btn-primary:focus-visible {
            outline: 3px solid rgba(37, 99, 235, 0.4);
            outline-offset: 2px;
        }

        .btn-secondary {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            background: #fff;
            color: var(--brand);
            border: 1.5px solid var(--brand);
            border-radius: 12px;
            padding: 9px 22px;
            font-size: 15px;
            font-weight: 600;
            transition: all 0.2s ease;
        }

        .btn-secondary:hover {
            background: var(--navbg);
            transform: translateY(-2px);
            box-shadow: 0 6px 16px rgba(37, 99, 235, 0.12);
        }

        /* 卡片 */
        .card {
            background: #fff;
            border: 1px solid var(--line);
            border-radius: 16px;
            box-shadow: 0 12px 30px -8px rgba(30, 64, 175, 0.10);
            transition: all 0.25s ease;
        }

        .card:hover {
            box-shadow: 0 20px 40px -12px rgba(30, 64, 175, 0.18);
            transform: translateY(-2px);
        }

        /* 区块标签 */
        .sec-tag {
            display: inline-block;
            background: #DBEAFE;
            color: var(--brand-dark);
            font-size: 13px;
            font-weight: 600;
            padding: 5px 14px;
            border-radius: 6px;
            letter-spacing: 0.03em;
        }

        /* 数据块 */
        .stat-num {
            font-size: 42px;
            font-weight: 800;
            line-height: 1.2;
            letter-spacing: -0.02em;
        }

        @media (max-width: 640px) {
            .stat-num {
                font-size: 32px;
            }
        }

        /* FAQ */
        .faq-item {
            background: #fff;
            border-radius: 16px;
            border: 1px solid var(--line);
            overflow: hidden;
            transition: border-color 0.2s ease;
        }

        .faq-item.open {
            border-color: var(--brand);
        }

        .faq-q {
            padding: 18px 22px;
            font-weight: 600;
            font-size: 16px;
            cursor: pointer;
            display: flex;
            justify-content: space-between;
            align-items: center;
            gap: 12px;
            color: var(--ink);
        }

        .faq-q:hover {
            background: #F8FAFC;
        }

        .faq-icon {
            width: 28px;
            height: 28px;
            border-radius: 8px;
            background: #DBEAFE;
            color: var(--brand);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 18px;
            font-weight: 700;
            flex-shrink: 0;
            transition: all 0.2s ease;
        }

        .faq-a {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.35s ease, padding 0.3s ease;
            color: var(--ink-soft);
            font-size: 15px;
            line-height: 1.75;
            padding: 0 22px;
        }

        .faq-item.open .faq-a {
            padding-bottom: 22px;
        }

        /* 页脚链接 */
        .footer-link {
            color: #94A3B8;
            transition: color 0.2s ease;
            font-size: 14px;
        }

        .footer-link:hover {
            color: #fff;
        }

        /* 表单 */
        .form-control {
            width: 100%;
            border: 1px solid var(--line);
            border-radius: 12px;
            padding: 10px 14px;
            font-size: 14px;
            color: var(--ink);
            background: #fff;
            transition: border-color 0.2s ease, box-shadow 0.2s ease;
        }

        .form-control:focus {
            outline: none;
            border-color: var(--brand);
            box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.12);
        }

        .form-label {
            font-size: 13px;
            font-weight: 600;
            color: var(--ink);
            margin-bottom: 6px;
            display: block;
        }

        /* 移动端菜单 */
        .mobile-menu {
            background: #fff;
            border-radius: 16px;
            border: 1px solid var(--line);
            padding: 16px;
            box-shadow: 0 20px 40px rgba(30, 64, 175, 0.12);
        }

        /* 弹层 */
        .modal-overlay {
            background: rgba(15, 23, 42, 0.5);
            backdrop-filter: blur(4px);
        }

        @media (max-width: 640px) {
            .modal-panel {
                position: fixed;
                bottom: 0;
                left: 0;
                right: 0;
                border-radius: 20px 20px 0 0;
                max-height: 92vh;
                overflow-y: auto;
            }
        }

/* roulang page: category1 */
:root {
            --primary: #2563EB;
            --primary-dark: #1D4ED8;
            --accent: #D97706;
            --bg: #F8FAFC;
            --card: #FFFFFF;
            --nav-bg: #EFF6FF;
            --ink: #1E293B;
            --text-secondary: #64748B;
            --text-muted: #94A3B8;
            --border: #E2E8F0;
            --section-divider: #F1F5F9;
            --footer-bg: #0F1E3C;
            --radius: 0.75rem;
            --radius-lg: 1rem;
            --radius-xl: 1.25rem;
            --shadow-card: 0 12px 30px -8px rgba(30, 64, 175, 0.10);
            --shadow-hover: 0 20px 40px -12px rgba(30, 64, 175, 0.18);
        }
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        html {
            scroll-behavior: smooth;
        }
        body {
            font-family: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans CJK SC', system-ui, sans-serif;
            background: var(--bg);
            color: var(--ink);
            line-height: 1.7;
            -webkit-font-smoothing: antialiased;
        }
        img {
            max-width: 100%;
            display: block;
        }
        a {
            color: inherit;
            text-decoration: none;
        }
        button {
            cursor: pointer;
            background: none;
            border: none;
            font-family: inherit;
        }
        input,
        select,
        textarea {
            font-family: inherit;
            font-size: 14px;
            color: var(--ink);
        }
        .container-x {
            max-width: 1280px;
            margin: 0 auto;
            padding-left: 16px;
            padding-right: 16px;
        }
        @media (min-width: 768px) {
            .container-x {
                padding-left: 24px;
                padding-right: 24px;
            }
        }
        .nav-card {
            background: var(--nav-bg);
            border-radius: var(--radius-xl);
            border: 1px solid var(--border);
            box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
        }
        .nav-link {
            display: inline-flex;
            align-items: center;
            gap: 6px;
            padding: 8px 14px;
            border-radius: var(--radius);
            background: #fff;
            border: 1px solid var(--border);
            color: var(--ink);
            font-size: 14px;
            font-weight: 500;
            transition: all .2s ease;
            white-space: nowrap;
        }
        .nav-link:hover {
            background: #DBEAFE;
            border-color: var(--primary);
            color: var(--primary);
        }
        .nav-link.active {
            background: #DBEAFE;
            border-color: var(--primary);
            color: var(--primary);
            font-weight: 600;
        }
        .btn-primary {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 10px 22px;
            background: var(--primary);
            color: #fff;
            border-radius: var(--radius);
            font-size: 15px;
            font-weight: 600;
            transition: all .2s ease;
            border: none;
        }
        .btn-primary:hover {
            background: var(--primary-dark);
            transform: translateY(-2px);
            box-shadow: var(--shadow-hover);
        }
        .btn-primary:focus-visible {
            outline: 3px solid rgba(37, 99, 235, .4);
            outline-offset: 2px;
        }
        .btn-secondary {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 10px 22px;
            background: #fff;
            color: var(--primary);
            border: 1px solid var(--primary);
            border-radius: var(--radius);
            font-size: 15px;
            font-weight: 600;
            transition: all .2s ease;
        }
        .btn-secondary:hover {
            background: var(--nav-bg);
            transform: translateY(-2px);
            box-shadow: var(--shadow-card);
        }
        .btn-secondary:focus-visible {
            outline: 3px solid rgba(37, 99, 235, .3);
            outline-offset: 2px;
        }
        .badge-tag {
            display: inline-block;
            padding: 4px 12px;
            background: #DBEAFE;
            color: var(--primary);
            border-radius: 6px;
            font-size: 13px;
            font-weight: 600;
            letter-spacing: 0.02em;
        }
        .section-head {
            margin-bottom: 36px;
        }
        .section-head h2 {
            font-size: 30px;
            font-weight: 700;
            color: var(--ink);
            margin-top: 12px;
            letter-spacing: -0.02em;
            line-height: 1.3;
        }
        .section-head p {
            color: var(--text-secondary);
            font-size: 16px;
            margin-top: 8px;
        }
        @media (max-width: 768px) {
            .section-head h2 {
                font-size: 24px;
            }
        }
        .feature-card {
            background: var(--card);
            border: 1px solid var(--border);
            border-radius: var(--radius-xl);
            padding: 28px;
            box-shadow: var(--shadow-card);
            transition: all .25s ease;
            height: 100%;
        }
        .feature-card:hover {
            transform: translateY(-3px);
            box-shadow: var(--shadow-hover);
            border-color: #BFDBFE;
        }
        .feature-card-sm {
            background: var(--card);
            border: 1px solid var(--border);
            border-radius: var(--radius-lg);
            padding: 22px;
            box-shadow: var(--shadow-card);
            transition: all .25s ease;
            display: flex;
            gap: 14px;
            align-items: flex-start;
        }
        .feature-card-sm:hover {
            border-color: var(--primary);
            box-shadow: var(--shadow-hover);
            transform: translateX(4px);
        }
        .feature-icon {
            width: 44px;
            height: 44px;
            border-radius: 12px;
            background: #EFF6FF;
            color: var(--primary);
            display: flex;
            align-items: center;
            justify-content: center;
            flex-shrink: 0;
        }
        .feature-icon svg {
            width: 22px;
            height: 22px;
        }
        .cta-block {
            background: linear-gradient(135deg, var(--primary) 0%, #3B82F6 100%);
            border-radius: var(--radius-xl);
            padding: 52px 32px;
            text-align: center;
            color: #fff;
            position: relative;
            overflow: hidden;
        }
        .cta-block::before {
            content: '';
            position: absolute;
            width: 260px;
            height: 260px;
            border-radius: 50%;
            background: rgba(255, 255, 255, 0.08);
            top: -80px;
            right: -80px;
        }
        .cta-block::after {
            content: '';
            position: absolute;
            width: 180px;
            height: 180px;
            border-radius: 50%;
            background: rgba(255, 255, 255, 0.06);
            bottom: -60px;
            left: -40px;
        }
        .cta-block h2 {
            font-size: 30px;
            font-weight: 700;
            line-height: 1.3;
            position: relative;
            z-index: 1;
        }
        .cta-block p {
            color: rgba(255, 255, 255, 0.85);
            margin-top: 10px;
            font-size: 16px;
            position: relative;
            z-index: 1;
        }
        .cta-block .btn-light {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 12px 28px;
            background: #fff;
            color: var(--primary);
            border-radius: var(--radius);
            font-size: 15px;
            font-weight: 600;
            margin-top: 28px;
            transition: all .2s ease;
            position: relative;
            z-index: 1;
            border: none;
        }
        .cta-block .btn-light:hover {
            background: #EFF6FF;
            transform: translateY(-2px);
            box-shadow: 0 12px 24px -8px rgba(0, 0, 0, 0.2);
        }
        @media (max-width: 768px) {
            .cta-block {
                padding: 40px 20px;
            }
            .cta-block h2 {
                font-size: 24px;
            }
        }
        .breadcrumb {
            display: flex;
            align-items: center;
            gap: 8px;
            font-size: 14px;
            color: var(--text-muted);
            padding: 10px 16px;
            background: #F1F5F9;
            border-radius: 10px;
            margin-top: 20px;
        }
        .breadcrumb a {
            color: var(--text-secondary);
            transition: color .2s;
        }
        .breadcrumb a:hover {
            color: var(--primary);
        }
        .breadcrumb .current {
            color: var(--primary);
            font-weight: 500;
        }
        .footer-link {
            color: rgba(191, 219, 254, 0.6);
            font-size: 14px;
            transition: color .2s ease;
        }
        .footer-link:hover {
            color: #fff;
        }
        .modal-overlay {
            position: fixed;
            inset: 0;
            background: rgba(15, 23, 42, 0.5);
            z-index: 200;
            display: flex;
            align-items: center;
            justify-content: center;
            padding: 16px;
            backdrop-filter: blur(4px);
        }
        .modal-panel {
            background: #fff;
            border-radius: var(--radius-xl);
            max-width: 480px;
            width: 100%;
            padding: 36px 32px 28px;
            position: relative;
            max-height: 90vh;
            overflow-y: auto;
            box-shadow: 0 24px 60px -12px rgba(15, 23, 42, 0.3);
        }
        .modal-close {
            position: absolute;
            top: 16px;
            right: 16px;
            width: 34px;
            height: 34px;
            border-radius: 10px;
            display: flex;
            align-items: center;
            justify-content: center;
            background: #F1F5F9;
            color: var(--text-secondary);
            transition: all .2s;
            font-size: 18px;
            line-height: 1;
        }
        .modal-close:hover {
            background: #E2E8F0;
            color: var(--ink);
        }
        .modal-panel h3 {
            font-size: 20px;
            font-weight: 700;
            color: var(--ink);
            margin-bottom: 6px;
        }
        .modal-panel .modal-sub {
            font-size: 14px;
            color: var(--text-secondary);
            margin-bottom: 24px;
        }
        .form-group {
            margin-bottom: 16px;
        }
        .form-group label {
            display: block;
            font-size: 13px;
            font-weight: 500;
            color: var(--ink);
            margin-bottom: 6px;
        }
        .form-control {
            width: 100%;
            padding: 10px 14px;
            border: 1px solid var(--border);
            border-radius: 10px;
            background: #F8FAFC;
            transition: all .2s;
            font-size: 14px;
        }
        .form-control:focus {
            outline: none;
            border-color: var(--primary);
            background: #fff;
            box-shadow: 0 0 0 3px rgba(37, 99, 235, .12);
        }
        .privacy-note {
            font-size: 12px;
            color: var(--text-muted);
            margin-top: 16px;
            text-align: center;
            line-height: 1.6;
        }
        .hidden {
            display: none !important;
        }
        .hero-content h1 {
            font-size: 44px;
            font-weight: 800;
            letter-spacing: -0.03em;
            line-height: 1.2;
            margin: 16px 0 16px;
            color: var(--ink);
        }
        .hero-content .lead {
            font-size: 17px;
            color: var(--text-secondary);
            max-width: 560px;
            line-height: 1.8;
        }
        @media (max-width: 768px) {
            .hero-content h1 {
                font-size: 30px;
            }
            .hero-content .lead {
                font-size: 15px;
            }
        }
        .content-block h2 {
            font-size: 26px;
            font-weight: 700;
            color: var(--ink);
            margin-bottom: 14px;
            letter-spacing: -0.01em;
            position: relative;
            padding-left: 16px;
            border-left: 4px solid var(--primary);
            line-height: 1.4;
        }
        .content-block p {
            color: var(--text-secondary);
            font-size: 16px;
            line-height: 1.9;
            margin-bottom: 16px;
        }
        .content-block .img-wrap {
            border-radius: var(--radius-xl);
            overflow: hidden;
            margin: 24px 0;
            border: 1px solid var(--border);
            box-shadow: var(--shadow-card);
        }
        .content-block .img-wrap img {
            width: 100%;
            height: auto;
            object-fit: cover;
        }
        @media (max-width: 768px) {
            .content-block h2 {
                font-size: 22px;
            }
            .content-block p {
                font-size: 15px;
            }
        }
        .point-card {
            background: var(--card);
            border: 1px solid var(--border);
            border-radius: var(--radius-lg);
            padding: 24px;
            box-shadow: var(--shadow-card);
            transition: all .25s ease;
        }
        .point-card:hover {
            box-shadow: var(--shadow-hover);
            border-color: #BFDBFE;
        }
        .point-card .num {
            font-size: 32px;
            font-weight: 800;
            color: var(--primary);
            line-height: 1;
            margin-bottom: 8px;
        }
        .point-card h3 {
            font-size: 17px;
            font-weight: 600;
            margin-bottom: 8px;
        }
        .point-card p {
            font-size: 14px;
            color: var(--text-secondary);
            line-height: 1.7;
        }

/* roulang page: category2 */
:root {
            --brand: #2563EB;
            --brand-hover: #1D4ED8;
            --brand-light: #DBEAFE;
            --accent: #D97706;
            --bg: #F8FAFC;
            --card: #FFFFFF;
            --nav-bg: #EFF6FF;
            --ink: #1E293B;
            --text-sub: #64748B;
            --text-weak: #94A3B8;
            --line: #E2E8F0;
            --section-line: #F1F5F9;
            --footer-bg: #0F1E3C;
            --radius-lg: 16px;
            --radius-xl: 20px;
            --shadow-card: 0 12px 30px -8px rgba(30, 64, 175, 0.10);
            --shadow-card-hover: 0 20px 40px -12px rgba(30, 64, 175, 0.18);
        }

        * {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }

        html {
            scroll-behavior: smooth;
        }

        body {
            font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", system-ui, sans-serif;
            background-color: var(--bg);
            color: var(--ink);
            line-height: 1.6;
            -webkit-font-smoothing: antialiased;
        }

        a {
            text-decoration: none;
            color: inherit;
        }

        img {
            max-width: 100%;
            display: block;
        }

        button {
            font-family: inherit;
            border: none;
            background: none;
            cursor: pointer;
        }

        input, select, textarea {
            font-family: inherit;
        }

        .container-x {
            max-width: 1280px;
            margin: 0 auto;
            padding-left: 16px;
            padding-right: 16px;
        }

        @media (min-width: 768px) {
            .container-x {
                padding-left: 24px;
                padding-right: 24px;
            }
        }

        .nav-card {
            background: var(--nav-bg);
            border: 1px solid var(--line);
            border-radius: 20px;
            box-shadow: 0 4px 16px rgba(30, 64, 175, 0.06);
        }

        .nav-link {
            display: inline-flex;
            align-items: center;
            gap: 6px;
            padding: 8px 16px;
            border-radius: 12px;
            font-size: 14px;
            font-weight: 500;
            color: var(--text-sub);
            background: var(--card);
            border: 1px solid var(--line);
            transition: all 0.2s ease;
            white-space: nowrap;
        }

        .nav-link:hover {
            background: var(--brand-light);
            border-color: var(--brand);
            color: var(--brand);
        }

        .nav-link.active {
            background: var(--brand-light);
            border-color: var(--brand);
            color: var(--brand);
            font-weight: 600;
        }

        .btn-primary {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            background: var(--brand);
            color: #fff;
            font-size: 15px;
            font-weight: 600;
            padding: 10px 24px;
            border-radius: 12px;
            transition: all 0.2s ease;
            box-shadow: 0 4px 12px rgba(37, 99, 235, 0.25);
        }

        .btn-primary:hover {
            background: var(--brand-hover);
            transform: translateY(-2px);
            box-shadow: 0 8px 20px rgba(37, 99, 235, 0.35);
        }

        .btn-primary:focus-visible {
            outline: 3px solid rgba(37, 99, 235, 0.4);
            outline-offset: 2px;
        }

        .btn-secondary {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            background: #fff;
            color: var(--brand);
            font-size: 15px;
            font-weight: 600;
            padding: 10px 24px;
            border-radius: 12px;
            border: 1.5px solid var(--brand);
            transition: all 0.2s ease;
        }

        .btn-secondary:hover {
            background: var(--nav-bg);
            transform: translateY(-2px);
        }

        .btn-secondary:focus-visible {
            outline: 3px solid rgba(37, 99, 235, 0.4);
            outline-offset: 2px;
        }

        .section-tag {
            display: inline-block;
            background: var(--brand-light);
            color: var(--brand);
            font-size: 13px;
            font-weight: 600;
            padding: 4px 14px;
            border-radius: 99px;
            letter-spacing: 0.02em;
        }

        .section-title {
            font-size: 30px;
            font-weight: 700;
            letter-spacing: -0.02em;
            color: var(--ink);
            line-height: 1.25;
            margin-top: 12px;
        }

        .section-subtitle {
            font-size: 16px;
            color: var(--text-sub);
            margin-top: 10px;
            max-width: 560px;
        }

        .card {
            background: var(--card);
            border: 1px solid var(--line);
            border-radius: 20px;
            box-shadow: var(--shadow-card);
            transition: all 0.25s ease;
        }

        .card:hover {
            box-shadow: var(--shadow-card-hover);
            transform: translateY(-2px);
        }

        .mobile-nav-link {
            display: flex;
            align-items: center;
            gap: 10px;
            padding: 12px 16px;
            border-radius: 12px;
            font-size: 15px;
            font-weight: 500;
            color: var(--text-sub);
            background: var(--bg);
            border: 1px solid var(--line);
            transition: all 0.2s;
        }

        .mobile-nav-link:hover {
            background: var(--brand-light);
            border-color: var(--brand);
            color: var(--brand);
        }

        .mobile-nav-link.active {
            background: var(--brand-light);
            border-color: var(--brand);
            color: var(--brand);
            font-weight: 600;
        }

        .footer-link {
            color: rgba(191, 211, 255, 0.6);
            font-size: 14px;
            transition: color 0.2s;
        }

        .footer-link:hover {
            color: #ffffff;
        }

        .faq-item {
            background: var(--card);
            border: 1px solid var(--line);
            border-radius: 20px;
            box-shadow: var(--shadow-card);
            transition: box-shadow 0.2s;
        }

        .faq-item:hover {
            box-shadow: var(--shadow-card-hover);
        }

        .faq-question {
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 16px;
            padding: 20px 24px;
            cursor: pointer;
            font-size: 18px;
            font-weight: 600;
            color: var(--ink);
        }

        .faq-icon {
            flex-shrink: 0;
            width: 28px;
            height: 28px;
            border-radius: 50%;
            background: var(--brand-light);
            display: flex;
            align-items: center;
            justify-content: center;
            color: var(--brand);
            font-size: 18px;
            transition: transform 0.3s;
        }

        .faq-item.open .faq-icon {
            transform: rotate(45deg);
        }

        .faq-answer {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.35s ease;
        }

        .faq-item.open .faq-answer {
            max-height: 300px;
        }

        .faq-answer-inner {
            padding: 0 24px 20px;
            color: var(--text-sub);
            font-size: 15px;
            line-height: 1.7;
        }

        .hero-banner {
            background: linear-gradient(135deg, rgba(255, 255, 255, 0.92) 0%, rgba(239, 246, 255, 0.92) 60%, rgba(219, 234, 254, 0.85) 100%);
            position: relative;
            overflow: hidden;
        }

        .hero-banner-bg {
            position: absolute;
            inset: 0;
            background-image: url('/assets/images/backpic/back-2.png');
            background-size: cover;
            background-position: center;
            opacity: 0.35;
            z-index: 0;
        }

        .hero-banner-content {
            position: relative;
            z-index: 1;
        }

        .alt-block-img {
            border-radius: 20px;
            overflow: hidden;
            box-shadow: var(--shadow-card);
            border: 1px solid var(--line);
        }

        .alt-block-img img {
            width: 100%;
            height: 260px;
            object-fit: cover;
        }

        .modal-overlay {
            position: fixed;
            inset: 0;
            background: rgba(15, 23, 42, 0.5);
            display: none;
            align-items: center;
            justify-content: center;
            z-index: 100;
            padding: 16px;
        }

        .modal-overlay.show {
            display: flex;
        }

        .modal-box {
            background: #fff;
            border-radius: 20px;
            max-width: 480px;
            width: 100%;
            padding: 32px;
            position: relative;
            max-height: 90vh;
            overflow-y: auto;
        }

        .modal-close {
            position: absolute;
            top: 14px;
            right: 14px;
            width: 32px;
            height: 32px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            background: var(--bg);
            color: var(--text-sub);
            transition: all 0.2s;
        }

        .modal-close:hover {
            background: var(--brand-light);
            color: var(--brand);
        }

        .form-input {
            width: 100%;
            border: 1px solid var(--line);
            border-radius: 12px;
            padding: 10px 14px;
            font-size: 15px;
            background: var(--bg);
            color: var(--ink);
            transition: border-color 0.2s;
        }

        .form-input:focus {
            outline: none;
            border-color: var(--brand);
            background: #fff;
        }

        select.form-input {
            appearance: none;
            background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%2394A3B8' stroke-width='2'%3E%3Cpath d='M6 9l6 6 6-6'/%3E%3C/svg%3E");
            background-repeat: no-repeat;
            background-position: right 14px center;
        }

        @media (max-width: 640px) {
            .section-title {
                font-size: 24px;
            }
            .faq-question {
                font-size: 16px;
                padding: 16px 18px;
            }
            .faq-answer-inner {
                padding: 0 18px 16px;
            }
            .modal-box {
                padding: 24px;
                border-radius: 16px;
                align-self: flex-end;
                margin-top: auto;
                margin-bottom: auto;
                border-bottom-left-radius: 0;
                border-bottom-right-radius: 0;
            }
        }

/* roulang page: article */
:root {
            --brand: #2563EB;
            --brand-dark: #1D4ED8;
            --brand-light: #EFF6FF;
            --brand-faint: #DBEAFE;
            --accent: #D97706;
            --bg: #F8FAFC;
            --card: #FFFFFF;
            --ink: #1E293B;
            --muted: #64748B;
            --faint: #94A3B8;
            --line: #E2E8F0;
            --footer-bg: #0F1E3C;
            --shadow-card: 0 12px 30px -8px rgba(30, 64, 175, 0.10);
            --shadow-card-hover: 0 20px 40px -12px rgba(30, 64, 175, 0.18);
        }

        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        html {
            scroll-behavior: smooth;
        }

        body {
            font-family: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans CJK SC', system-ui, -apple-system, sans-serif;
            background: var(--bg);
            color: var(--ink);
            line-height: 1.6;
            -webkit-font-smoothing: antialiased;
        }

        a {
            color: inherit;
            text-decoration: none;
        }

        img {
            display: block;
            max-width: 100%;
        }

        button {
            font-family: inherit;
            cursor: pointer;
            border: none;
            background: none;
        }

        ul,
        ol {
            list-style: none;
        }

        a:focus-visible,
        button:focus-visible,
        input:focus-visible,
        select:focus-visible,
        textarea:focus-visible {
            outline: 2px solid var(--brand);
            outline-offset: 2px;
            border-radius: 0.375rem;
        }

        .container-x {
            max-width: 1280px;
            margin-left: auto;
            margin-right: auto;
            padding-left: 16px;
            padding-right: 16px;
        }

        @media (min-width: 768px) {
            .container-x {
                padding-left: 24px;
                padding-right: 24px;
            }
        }

        /* ===== 导航 ===== */
        .nav-card {
            background: var(--brand-light);
            border-radius: 1.25rem;
            box-shadow: 0 4px 20px rgba(30, 64, 175, 0.08);
            border: 1px solid #DBEAFE;
        }

        .nav-link {
            display: inline-flex;
            align-items: center;
            gap: 0.5rem;
            padding: 0.5rem 0.875rem;
            border-radius: 0.75rem;
            background: #ffffff;
            border: 1px solid #E2E8F0;
            color: #334155;
            font-size: 0.875rem;
            font-weight: 500;
            white-space: nowrap;
            transition: all 0.2s ease;
        }

        .nav-link:hover {
            background: #DBEAFE;
            border-color: var(--brand);
            color: var(--brand);
        }

        .nav-link.active {
            background: #DBEAFE;
            border-color: var(--brand);
            color: var(--brand-dark);
            font-weight: 600;
            box-shadow: 0 2px 8px rgba(37, 99, 235, 0.12);
        }

        .nav-link svg {
            flex-shrink: 0;
        }

        .btn-primary {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 0.5rem;
            padding: 0.625rem 1.25rem;
            background: var(--brand);
            color: #ffffff !important;
            border-radius: 0.75rem;
            font-weight: 600;
            font-size: 0.875rem;
            line-height: 1;
            white-space: nowrap;
            transition: all 0.2s ease;
            box-shadow: 0 4px 12px rgba(37, 99, 235, 0.25);
        }

        .btn-primary:hover {
            background: var(--brand-dark);
            transform: translateY(-2px);
            box-shadow: 0 8px 20px rgba(37, 99, 235, 0.30);
        }

        .btn-primary:active {
            transform: translateY(0);
        }

        .btn-outline {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 0.5rem;
            padding: 0.625rem 1.25rem;
            background: #ffffff;
            color: var(--brand);
            border: 1px solid var(--brand);
            border-radius: 0.75rem;
            font-weight: 600;
            font-size: 0.875rem;
            transition: all 0.2s ease;
        }

        .btn-outline:hover {
            background: var(--brand-light);
            transform: translateY(-2px);
        }

        #mobileMenu.hidden {
            display: none;
        }

        /* ===== 面包屑 ===== */
        .breadcrumb a {
            color: var(--muted);
            transition: color 0.2s ease;
        }

        .breadcrumb a:hover {
            color: var(--brand);
        }

        .breadcrumb .breadcrumb-current {
            display: inline-block;
            max-width: 200px;
            overflow: hidden;
            text-overflow: ellipsis;
            white-space: nowrap;
            vertical-align: bottom;
        }

        /* ===== 文章头部 ===== */
        .article-header {
            background: linear-gradient(180deg, #ffffff 0%, #F8FAFC 100%);
            border-bottom: 1px solid var(--line);
        }

        .category-tag {
            display: inline-flex;
            align-items: center;
            gap: 0.4rem;
            background: #DBEAFE;
            color: var(--brand-dark);
            font-size: 0.8125rem;
            font-weight: 600;
            padding: 0.3125rem 0.75rem;
            border-radius: 9999px;
            border: 1px solid #BFDBFE;
        }

        .article-meta-sep {
            color: var(--faint);
            margin: 0 0.375rem;
        }

        /* ===== 正文排版 ===== */
        .article-body {
            font-size: 1.0625rem;
            line-height: 1.8;
            color: #334155;
        }

        .article-body p {
            margin-bottom: 1.5rem;
        }

        .article-body strong {
            font-weight: 600;
            color: var(--ink);
        }

        .article-body h2 {
            font-size: 1.5rem;
            font-weight: 700;
            color: var(--ink);
            margin: 2.75rem 0 1.25rem;
            padding-left: 0.875rem;
            border-left: 4px solid var(--brand);
            line-height: 1.4;
        }

        .article-body h3 {
            font-size: 1.25rem;
            font-weight: 600;
            color: var(--ink);
            margin: 2rem 0 0.875rem;
            line-height: 1.5;
        }

        .article-body ul,
        .article-body ol {
            margin: 1.25rem 0 1.5rem;
            padding-left: 1.5rem;
        }

        .article-body ul {
            list-style: disc;
        }

        .article-body ol {
            list-style: decimal;
        }

        .article-body li {
            margin-bottom: 0.5rem;
        }

        .article-body blockquote {
            background: #EFF6FF;
            border: 1px solid #DBEAFE;
            border-left-width: 4px;
            border-left-color: var(--brand);
            border-radius: 0.75rem;
            padding: 1.25rem 1.5rem;
            margin: 1.75rem 0;
            color: #1E40AF;
        }

        .article-body a {
            color: var(--brand);
            text-decoration: underline;
            text-underline-offset: 3px;
            transition: color 0.2s ease;
        }

        .article-body a:hover {
            color: var(--brand-dark);
        }

        .article-body img {
            border-radius: 1rem;
            margin: 2rem auto;
            max-width: 100%;
            height: auto;
        }

        .article-body table {
            width: 100%;
            border-collapse: collapse;
            margin: 1.75rem 0;
            border-radius: 0.75rem;
            overflow: hidden;
            font-size: 0.9375rem;
        }

        .article-body table th,
        .article-body table td {
            border: 1px solid var(--line);
            padding: 0.75rem 1rem;
            text-align: left;
        }

        .article-body table th {
            background: #EFF6FF;
            font-weight: 600;
            color: var(--ink);
        }

        /* ===== 图片占位 ===== */
        .img-fallback {
            display: none;
            align-items: center;
            justify-content: center;
            flex-direction: column;
            gap: 0.75rem;
            background: #EFF6FF;
            color: var(--faint);
            font-size: 0.875rem;
            aspect-ratio: 16 / 9;
            border-radius: 1rem;
        }

        .img-fallback.show {
            display: flex;
        }

        /* ===== 相关推荐卡片 ===== */
        .related-card {
            background: var(--card);
            border-radius: 1rem;
            border: 1px solid var(--line);
            box-shadow: var(--shadow-card);
            overflow: hidden;
            transition: all 0.25s ease;
        }

        .related-card:hover {
            box-shadow: var(--shadow-card-hover);
            transform: translateY(-4px);
        }

        .related-card .related-thumb {
            aspect-ratio: 16 / 9;
            width: 100%;
            object-fit: cover;
            border-radius: 1rem 1rem 0 0;
        }

        .related-card .related-body {
            padding: 1.25rem 1.5rem;
        }

        /* ===== 表单弹层 ===== */
        .modal-overlay {
            position: fixed;
            inset: 0;
            background: rgba(15, 23, 42, 0.5);
            z-index: 100;
            display: flex;
            align-items: center;
            justify-content: center;
            padding: 1rem;
        }

        .modal-overlay.hidden {
            display: none;
        }

        .modal-card {
            position: relative;
            background: #ffffff;
            border-radius: 1.25rem;
            max-width: 480px;
            width: 100%;
            padding: 2rem;
            max-height: 90vh;
            overflow-y: auto;
        }

        .modal-card .close-btn {
            position: absolute;
            top: 1rem;
            right: 1rem;
            width: 2.25rem;
            height: 2.25rem;
            display: flex;
            align-items: center;
            justify-content: center;
            background: #F1F5F9;
            color: #64748B;
            border-radius: 0.75rem;
            transition: all 0.2s ease;
        }

        .modal-card .close-btn:hover {
            background: #E2E8F0;
            color: #1E293B;
        }

        .form-input {
            width: 100%;
            border: 1px solid var(--line);
            border-radius: 0.75rem;
            padding: 0.75rem 1rem;
            font-size: 0.9375rem;
            background: #F8FAFC;
            color: var(--ink);
            transition: border-color 0.2s ease, box-shadow 0.2s ease, background-color 0.2s ease;
        }

        .form-input:focus {
            outline: none;
            border-color: var(--brand);
            box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.10);
            background: #ffffff;
        }

        .form-input::placeholder {
            color: var(--faint);
        }

        .privacy-note {
            font-size: 0.75rem;
            color: var(--faint);
            margin-top: 1rem;
            text-align: center;
            line-height: 1.6;
        }

        @media (max-width: 640px) {
            .modal-overlay {
                align-items: flex-end;
                padding: 0;
            }

            .modal-card {
                border-radius: 1.25rem 1.25rem 0 0;
                max-width: 100%;
                padding: 1.5rem;
            }
        }

        /* ===== 页脚 ===== */
        .footer-link {
            color: rgba(191, 219, 254, 0.60);
            font-size: 0.875rem;
            transition: color 0.2s ease;
        }

        .footer-link:hover {
            color: #ffffff;
        }