/* roulang page: index */
:root {
            --brand: #2563EB;
            --brand-hover: #1D4ED8;
            --brand-light: #EFF6FF;
            --copper: #B45309;
            --bg: #F5F7FB;
            --surface: #FFFFFF;
            --ink: #0F172A;
            --sub: #64748B;
            --line: #E2E8F0;
            --radius-card: 18px;
            --radius-btn: 13px;
            --shadow-card: 0 10px 30px rgba(15, 23, 42, 0.06);
            --shadow-card-hover: 0 16px 40px rgba(15, 23, 42, 0.10);
            --shadow-nav: 0 2px 12px rgba(15, 23, 42, 0.06);
        }

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

        html {
            scroll-behavior: smooth;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }

        body {
            font-family: 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', system-ui, sans-serif;
            background-color: var(--bg);
            color: var(--ink);
            line-height: 1.7;
            font-size: 15px;
            overflow-x: hidden;
        }

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

        a {
            text-decoration: none;
            color: inherit;
            transition: color 0.2s ease;
        }

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

        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 24px;
        }

        /* Header */
        .site-header {
            position: sticky;
            top: 0;
            z-index: 100;
            background: rgba(255, 255, 255, 0.92);
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            border-bottom: 1px solid var(--line);
            box-shadow: var(--shadow-nav);
        }

        .header-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            height: 64px;
            gap: 16px;
        }

        .logo-text {
            font-size: 18px;
            font-weight: 800;
            color: var(--ink);
            letter-spacing: -0.02em;
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
            max-width: 260px;
        }

        .logo-text .logo-accent {
            color: var(--brand);
        }

        .nav-desktop {
            display: flex;
            align-items: center;
            gap: 4px;
        }

        .nav-desktop>li {
            list-style: none;
            position: relative;
        }

        .nav-desktop>li>a,
        .nav-desktop>li>button {
            display: inline-flex;
            align-items: center;
            gap: 4px;
            padding: 8px 14px;
            font-size: 14px;
            font-weight: 500;
            color: var(--ink);
            border-radius: 10px;
            cursor: pointer;
            background: none;
            border: none;
            transition: all 0.2s;
            white-space: nowrap;
        }

        .nav-desktop>li>a:hover,
        .nav-desktop>li>button:hover {
            background: var(--brand-light);
            color: var(--brand);
        }

        .nav-desktop>li.active>a {
            background: var(--brand-light);
            color: var(--brand);
            font-weight: 600;
        }

        .nav-arrow {
            width: 16px;
            height: 16px;
            fill: currentColor;
            transition: transform 0.25s;
        }

        .nav-desktop li:hover .nav-arrow {
            transform: rotate(180deg);
        }

        .dropdown-panel {
            position: absolute;
            top: calc(100% + 8px);
            left: 0;
            min-width: 280px;
            background: var(--surface);
            border: 1px solid var(--line);
            border-radius: 14px;
            box-shadow: var(--shadow-card-hover);
            padding: 10px 6px;
            opacity: 0;
            visibility: hidden;
            transform: translateY(8px);
            transition: all 0.25s;
            z-index: 50;
        }

        .nav-desktop>li:hover .dropdown-panel,
        .nav-desktop>li>a:focus+.dropdown-panel,
        .nav-desktop>li>button:focus+.dropdown-panel {
            opacity: 1;
            visibility: visible;
            transform: translateY(0);
        }

        .dropdown-panel .dp-title {
            font-size: 12px;
            font-weight: 600;
            color: var(--sub);
            text-transform: uppercase;
            letter-spacing: 0.04em;
            padding: 6px 12px 8px;
            border-bottom: 1px solid var(--line);
            margin-bottom: 6px;
        }

        .dropdown-panel .dp-list {
            list-style: none;
        }

        .dropdown-panel .dp-list li a {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 8px 12px;
            border-radius: 10px;
            font-size: 13px;
            color: var(--ink);
            transition: all 0.2s;
        }

        .dropdown-panel .dp-list li a:hover {
            background: var(--brand-light);
            color: var(--brand);
        }

        .dp-badge {
            font-size: 11px;
            background: var(--brand-light);
            color: var(--brand);
            padding: 2px 8px;
            border-radius: 999px;
            font-weight: 500;
        }

        /* Hamburger */
        .hamburger {
            display: none;
            flex-direction: column;
            gap: 5px;
            background: none;
            border: none;
            cursor: pointer;
            padding: 8px;
        }

        .hamburger span {
            display: block;
            width: 24px;
            height: 2px;
            background: var(--ink);
            border-radius: 4px;
            transition: all 0.3s;
        }

        .mobile-nav {
            display: none;
            background: var(--surface);
            border-top: 1px solid var(--line);
            padding: 16px 24px 24px;
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.4s;
        }

        .mobile-nav.open {
            display: block;
            max-height: 600px;
            overflow-y: auto;
        }

        .mobile-nav ul {
            list-style: none;
        }

        .mobile-nav ul li a,
        .mobile-nav ul li summary {
            display: block;
            padding: 12px 4px;
            font-size: 15px;
            font-weight: 500;
            color: var(--ink);
            border-bottom: 1px solid var(--line);
            cursor: pointer;
        }

        .mobile-nav ul li a:hover {
            color: var(--brand);
        }

        /* Buttons */
        .btn {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            padding: 12px 24px;
            border-radius: var(--radius-btn);
            font-weight: 600;
            font-size: 15px;
            border: 2px solid transparent;
            cursor: pointer;
            transition: all 0.25s;
            text-align: center;
            white-space: nowrap;
        }

        .btn-primary {
            background: var(--brand);
            color: #fff;
        }
        .btn-primary:hover {
            background: var(--brand-hover);
            transform: translateY(-1px);
        }
        .btn-primary:focus-visible {
            outline: 2px solid var(--brand);
            outline-offset: 2px;
        }

        .btn-secondary {
            background: var(--surface);
            color: var(--brand);
            border-color: var(--brand);
        }
        .btn-secondary:hover {
            background: var(--brand-light);
            transform: translateY(-1px);
        }
        .btn-secondary:focus-visible {
            outline: 2px solid var(--brand);
            outline-offset: 2px;
        }

        .btn-sm {
            padding: 8px 16px;
            font-size: 13px;
            border-radius: 10px;
        }

        /* Section */
        .section {
            padding: 80px 0;
        }

        .section-alt {
            background: var(--surface);
            border-top: 1px solid var(--line);
            border-bottom: 1px solid var(--line);
        }

        .section-title {
            font-size: 30px;
            font-weight: 700;
            letter-spacing: -0.01em;
            color: var(--ink);
            margin-bottom: 12px;
        }

        .section-desc {
            font-size: 16px;
            color: var(--sub);
            max-width: 720px;
            line-height: 1.8;
            margin-bottom: 32px;
        }

        /* Cards */
        .card {
            background: var(--surface);
            border-radius: var(--radius-card);
            box-shadow: var(--shadow-card);
            border: 1px solid var(--line);
            overflow: hidden;
            transition: all 0.3s;
        }

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

        .card-img {
            width: 100%;
            height: 200px;
            object-fit: cover;
        }

        .card-body {
            padding: 20px 22px;
        }

        .card-title {
            font-size: 19px;
            font-weight: 600;
            margin-bottom: 8px;
            color: var(--ink);
        }

        .card-text {
            font-size: 14px;
            color: var(--sub);
            line-height: 1.7;
            margin-bottom: 12px;
        }

        .card-meta {
            font-size: 12px;
            color: var(--sub);
            display: flex;
            align-items: center;
            gap: 8px;
            flex-wrap: wrap;
        }

        /* Badge */
        .badge {
            display: inline-flex;
            align-items: center;
            gap: 4px;
            padding: 4px 12px;
            font-size: 12px;
            font-weight: 600;
            border-radius: 999px;
            background: var(--brand-light);
            color: var(--brand);
        }

        .badge-copper {
            background: #FFF7ED;
            color: var(--copper);
        }

        .badge-outline {
            background: transparent;
            border: 1px solid var(--line);
            color: var(--sub);
        }

        /* Hero */
        .hero-section {
            padding: 64px 0 72px;
            position: relative;
            overflow: hidden;
        }

        .hero-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 48px;
            align-items: center;
        }

        .hero-title {
            font-size: 40px;
            font-weight: 800;
            letter-spacing: -0.02em;
            line-height: 1.25;
            color: var(--ink);
            margin-bottom: 16px;
        }

        .hero-sub {
            font-size: 16px;
            color: var(--sub);
            line-height: 1.8;
            margin-bottom: 24px;
            max-width: 520px;
        }

        .hero-actions {
            display: flex;
            gap: 12px;
            flex-wrap: wrap;
            margin-bottom: 24px;
        }

        .hero-stats {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 16px;
            margin-top: 32px;
        }

        .hero-stat {
            background: var(--surface);
            border-radius: 14px;
            padding: 16px 18px;
            text-align: center;
            border: 1px solid var(--line);
            box-shadow: var(--shadow-card);
        }

        .hero-stat-num {
            font-size: 28px;
            font-weight: 800;
            color: var(--brand);
            display: block;
            letter-spacing: -0.01em;
        }

        .hero-stat-num.copper {
            color: var(--copper);
            font-size: 24px;
        }

        .hero-stat-label {
            font-size: 12px;
            color: var(--sub);
            margin-top: 4px;
            display: block;
        }

        /* Before After */
        .ba-wrap {
            position: relative;
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 12px;
            background: var(--surface);
            border-radius: var(--radius-card);
            box-shadow: var(--shadow-card-hover);
            padding: 20px;
            border: 1px solid var(--line);
        }

        .ba-panel {
            border-radius: 12px;
            overflow: hidden;
            position: relative;
            background: #F8FAFC;
        }

        .ba-panel img {
            width: 100%;
            height: 220px;
            object-fit: cover;
        }

        .ba-label {
            position: absolute;
            top: 10px;
            left: 10px;
            background: rgba(15, 23, 42, 0.75);
            color: #fff;
            font-size: 11px;
            padding: 4px 10px;
            border-radius: 999px;
            font-weight: 600;
            letter-spacing: 0.03em;
        }

        .ba-divider {
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 24px;
            color: var(--brand);
            font-weight: 700;
            position: absolute;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%);
            background: var(--surface);
            width: 40px;
            height: 40px;
            border-radius: 50%;
            box-shadow: 0 4px 16px rgba(15, 23, 42, 0.12);
            z-index: 5;
            border: 2px solid var(--brand-light);
        }

        /* Matrix grid */
        .matrix-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 24px;
        }

        /* Compare table */
        .compare-table {
            width: 100%;
            border-collapse: separate;
            border-spacing: 0;
            background: var(--surface);
            border-radius: var(--radius-card);
            overflow: hidden;
            box-shadow: var(--shadow-card);
            border: 1px solid var(--line);
        }

        .compare-table th,
        .compare-table td {
            padding: 16px 20px;
            text-align: left;
            font-size: 14px;
            border-bottom: 1px solid var(--line);
        }

        .compare-table th {
            background: #F8FAFC;
            font-weight: 700;
            color: var(--ink);
            font-size: 13px;
            letter-spacing: 0.02em;
        }

        .compare-table tr:last-child td {
            border-bottom: none;
        }

        .compare-table .highlight-col {
            background: var(--brand-light);
            border-left: 3px solid var(--brand);
        }

        .compare-table .highlight-col th {
            background: var(--brand-light);
            color: var(--brand);
        }

        /* Timeline */
        .timeline {
            position: relative;
            padding-left: 28px;
        }

        .timeline::before {
            content: '';
            position: absolute;
            left: 8px;
            top: 8px;
            bottom: 8px;
            width: 2px;
            background: var(--line);
        }

        .timeline-item {
            position: relative;
            margin-bottom: 28px;
            padding-left: 20px;
        }

        .timeline-item::before {
            content: '';
            position: absolute;
            left: -28px;
            top: 6px;
            width: 14px;
            height: 14px;
            border-radius: 50%;
            background: var(--brand);
            border: 3px solid var(--surface);
            box-shadow: 0 0 0 2px var(--brand-light);
        }

        .timeline-item .tl-date {
            font-size: 13px;
            font-weight: 600;
            color: var(--copper);
            margin-bottom: 4px;
        }

        .timeline-item .tl-title {
            font-size: 16px;
            font-weight: 600;
            color: var(--ink);
            margin-bottom: 4px;
        }

        .timeline-item .tl-desc {
            font-size: 14px;
            color: var(--sub);
        }

        /* News list */
        .news-list {
            display: flex;
            flex-direction: column;
            gap: 16px;
        }

        .news-item {
            display: flex;
            gap: 20px;
            background: var(--surface);
            border-radius: 14px;
            padding: 16px;
            border: 1px solid var(--line);
            box-shadow: var(--shadow-card);
            transition: all 0.3s;
        }

        .news-item:hover {
            box-shadow: var(--shadow-card-hover);
            border-color: var(--brand);
            transform: translateY(-2px);
        }

        .news-item img {
            width: 180px;
            height: 120px;
            object-fit: cover;
            border-radius: 10px;
            flex-shrink: 0;
        }

        .news-content {
            flex: 1;
        }

        .news-title {
            font-size: 16px;
            font-weight: 600;
            color: var(--ink);
            margin-bottom: 6px;
        }

        .news-excerpt {
            font-size: 13px;
            color: var(--sub);
            line-height: 1.7;
            margin-bottom: 6px;
        }

        .news-date {
            font-size: 12px;
            color: var(--sub);
        }

        /* Feature list */
        .feature-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 20px;
        }

        .feature-item {
            display: flex;
            flex-direction: column;
            gap: 8px;
            padding: 20px;
            background: var(--surface);
            border-radius: 14px;
            border: 1px solid var(--line);
            transition: all 0.3s;
        }

        .feature-item:hover {
            border-color: var(--brand);
            box-shadow: var(--shadow-card);
        }

        .feature-icon {
            width: 40px;
            height: 40px;
            display: flex;
            align-items: center;
            justify-content: center;
            background: var(--brand-light);
            color: var(--brand);
            border-radius: 10px;
            font-size: 18px;
            font-weight: 700;
        }

        .feature-title {
            font-size: 15px;
            font-weight: 600;
            color: var(--ink);
        }

        .feature-desc {
            font-size: 13px;
            color: var(--sub);
            line-height: 1.6;
        }

        /* Tag cloud */
        .tag-cloud {
            display: flex;
            flex-wrap: wrap;
            gap: 10px;
        }

        .tag-btn {
            display: inline-flex;
            align-items: center;
            padding: 8px 18px;
            background: var(--surface);
            border: 1px solid var(--line);
            border-radius: 999px;
            font-size: 13px;
            font-weight: 500;
            color: var(--sub);
            cursor: pointer;
            transition: all 0.25s;
        }

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

        .tag-btn.hot {
            border-color: var(--copper);
            color: var(--copper);
            background: #FFF7ED;
        }

        /* FAQ */
        .faq-card {
            background: var(--surface);
            border-radius: 14px;
            border: 1px solid var(--line);
            box-shadow: var(--shadow-card);
            margin-bottom: 12px;
            overflow: hidden;
            transition: all 0.3s;
        }

        .faq-card summary {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 18px 20px;
            cursor: pointer;
            font-weight: 600;
            font-size: 15px;
            color: var(--ink);
            list-style: none;
        }

        .faq-card summary::-webkit-details-marker {
            display: none;
        }

        .faq-card summary .faq-arrow {
            width: 20px;
            height: 20px;
            flex-shrink: 0;
            transition: transform 0.3s;
            color: var(--sub);
        }

        .faq-card[open] summary .faq-arrow {
            transform: rotate(180deg);
        }

        .faq-card[open] {
            border-color: var(--brand);
            box-shadow: var(--shadow-card-hover);
        }

        .faq-answer {
            padding: 0 20px 18px;
            font-size: 14px;
            color: var(--sub);
            line-height: 1.8;
        }

        /* Form */
        .form-card {
            background: var(--surface);
            border-radius: var(--radius-card);
            padding: 28px;
            border: 1px solid var(--line);
            box-shadow: var(--shadow-card);
        }

        .form-label {
            display: block;
            font-size: 14px;
            font-weight: 600;
            color: var(--ink);
            margin-bottom: 6px;
        }

        .form-input,
        .form-select {
            width: 100%;
            padding: 12px 16px;
            border: 1px solid var(--line);
            border-radius: 10px;
            font-size: 14px;
            color: var(--ink);
            background: #F8FAFC;
            transition: all 0.25s;
            margin-bottom: 16px;
        }

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

        /* Footer */
        .site-footer {
            background: var(--surface);
            border-top: 1px solid var(--line);
            padding: 48px 0 24px;
            margin-top: 0;
        }

        .footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr 1fr;
            gap: 32px;
            margin-bottom: 32px;
        }

        .footer-brand {
            font-size: 17px;
            font-weight: 700;
            color: var(--ink);
            margin-bottom: 8px;
        }

        .footer-brand .logo-accent {
            color: var(--brand);
        }

        .footer-text {
            font-size: 13px;
            color: var(--sub);
            line-height: 1.7;
        }

        .footer-col-title {
            font-size: 14px;
            font-weight: 600;
            color: var(--ink);
            margin-bottom: 12px;
        }

        .footer-col ul {
            list-style: none;
        }

        .footer-col ul li {
            margin-bottom: 8px;
        }

        .footer-col ul li a {
            font-size: 13px;
            color: var(--sub);
            transition: color 0.2s;
        }

        .footer-col ul li a:hover {
            color: var(--brand);
        }

        .footer-bottom {
            border-top: 1px solid var(--line);
            padding-top: 16px;
            display: flex;
            align-items: center;
            justify-content: space-between;
            flex-wrap: wrap;
            gap: 8px;
            font-size: 12px;
            color: var(--sub);
        }

        /* Responsive */
        @media (max-width: 1024px) {
            .hero-grid {
                grid-template-columns: 1fr;
                gap: 32px;
            }
            .hero-title {
                font-size: 34px;
            }
            .hero-stats {
                grid-template-columns: repeat(2, 1fr);
            }
            .matrix-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .feature-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .footer-grid {
                grid-template-columns: 1fr 1fr;
                gap: 24px;
            }
        }

        @media (max-width: 768px) {
            .nav-desktop {
                display: none;
            }
            .hamburger {
                display: flex;
            }
            .mobile-nav.open {
                display: block;
            }
            .container {
                padding: 0 16px;
            }
            .section {
                padding: 48px 0;
            }
            .section-title {
                font-size: 26px;
            }
            .hero-title {
                font-size: 28px;
            }
            .hero-section {
                padding: 40px 0 48px;
            }
            .matrix-grid {
                grid-template-columns: 1fr;
            }
            .feature-grid {
                grid-template-columns: 1fr 1fr;
                gap: 12px;
            }
            .news-item {
                flex-direction: column;
            }
            .news-item img {
                width: 100%;
                height: 170px;
            }
            .compare-table th,
            .compare-table td {
                padding: 12px 14px;
                font-size: 13px;
            }
            .footer-grid {
                grid-template-columns: 1fr;
                gap: 20px;
            }
            .footer-bottom {
                flex-direction: column;
                align-items: flex-start;
            }
            .ba-wrap {
                grid-template-columns: 1fr;
            }
            .ba-divider {
                top: auto;
                bottom: -20px;
                left: 50%;
                transform: translateX(-50%) rotate(90deg);
            }
        }

        @media (max-width: 520px) {
            .hero-title {
                font-size: 24px;
            }
            .hero-stats {
                grid-template-columns: 1fr 1fr;
                gap: 8px;
            }
            .hero-stat {
                padding: 12px 10px;
            }
            .hero-stat-num {
                font-size: 22px;
            }
            .feature-grid {
                grid-template-columns: 1fr;
            }
            .card-img {
                height: 170px;
            }
            .btn {
                padding: 10px 18px;
                font-size: 14px;
            }
            .section-title {
                font-size: 22px;
            }
            .tag-btn {
                padding: 6px 14px;
                font-size: 12px;
            }
        }

/* roulang page: category1 */
:root {
            --brand: #2563EB;
            --brand-hover: #1D4ED8;
            --brand-light: #EFF6FF;
            --copper: #B45309;
            --bg: #F5F7FB;
            --surface: #FFFFFF;
            --ink: #0F172A;
            --sub: #64748B;
            --line: #E2E8F0;
            --radius-card: 18px;
            --radius-btn: 13px;
            --shadow-card: 0 10px 30px rgba(15, 23, 42, 0.06);
            --shadow-card-hover: 0 16px 40px rgba(15, 23, 42, 0.10);
            --shadow-nav: 0 2px 12px rgba(15, 23, 42, 0.06);
        }
        html {
            scroll-behavior: smooth;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }
        body {
            font-family: 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', system-ui, sans-serif;
            background-color: var(--bg);
            color: var(--ink);
            line-height: 1.7;
            font-size: 15px;
            overflow-x: hidden;
            margin: 0;
            padding: 0;
        }
        img {
            display: block;
            max-width: 100%;
            height: auto;
        }
        a {
            text-decoration: none;
            color: inherit;
            transition: color 0.2s ease;
        }
        button, input, select, textarea {
            font-family: inherit;
            font-size: inherit;
        }
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 24px;
        }
        /* Header */
        .site-header {
            position: sticky;
            top: 0;
            z-index: 100;
            background: rgba(255, 255, 255, 0.92);
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            border-bottom: 1px solid var(--line);
            box-shadow: var(--shadow-nav);
        }
        .header-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            height: 64px;
            gap: 16px;
        }
        .logo-text {
            font-size: 18px;
            font-weight: 800;
            color: var(--ink);
            letter-spacing: -0.02em;
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
            max-width: 280px;
        }
        .logo-text .logo-accent {
            color: var(--brand);
        }
        .nav-desktop {
            display: flex;
            align-items: center;
            gap: 4px;
            list-style: none;
            margin: 0;
            padding: 0;
        }
        .nav-desktop > li {
            list-style: none;
            position: relative;
        }
        .nav-desktop > li > a,
        .nav-desktop > li > button {
            display: inline-flex;
            align-items: center;
            gap: 4px;
            padding: 8px 14px;
            font-size: 14px;
            font-weight: 500;
            color: var(--ink);
            border-radius: 10px;
            cursor: pointer;
            background: none;
            border: none;
            transition: all 0.2s;
            white-space: nowrap;
        }
        .nav-desktop > li > a:hover,
        .nav-desktop > li > button:hover {
            background: var(--brand-light);
            color: var(--brand);
        }
        .nav-desktop > li.active > a {
            background: var(--brand-light);
            color: var(--brand);
            font-weight: 600;
        }
        .nav-arrow {
            width: 16px;
            height: 16px;
            fill: currentColor;
            transition: transform 0.25s;
        }
        .nav-desktop li:hover .nav-arrow {
            transform: rotate(180deg);
        }
        .dropdown-panel {
            position: absolute;
            top: 100%;
            left: 0;
            width: 280px;
            background: var(--surface);
            border: 1px solid var(--line);
            border-radius: 12px;
            box-shadow: var(--shadow-card);
            padding: 8px;
            opacity: 0;
            visibility: hidden;
            transform: translateY(8px);
            transition: all 0.25s;
            z-index: 200;
        }
        .nav-desktop li:hover .dropdown-panel,
        .nav-desktop li:focus-within .dropdown-panel {
            opacity: 1;
            visibility: visible;
            transform: translateY(0);
        }
        .dp-title {
            font-size: 12px;
            font-weight: 600;
            color: var(--sub);
            text-transform: uppercase;
            letter-spacing: 0.04em;
            padding: 6px 12px 8px;
            border-bottom: 1px solid var(--line);
            margin-bottom: 6px;
        }
        .dp-list {
            list-style: none;
            margin: 0;
            padding: 0;
        }
        .dp-list a {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 8px 12px;
            border-radius: 10px;
            font-size: 13px;
            color: var(--ink);
            transition: all 0.2s;
        }
        .dp-list a:hover {
            background: var(--brand-light);
            color: var(--brand);
        }
        .dp-badge {
            font-size: 11px;
            background: var(--brand-light);
            color: var(--brand);
            padding: 2px 8px;
            border-radius: 999px;
            font-weight: 500;
        }
        /* Hamburger */
        .hamburger {
            display: none;
            flex-direction: column;
            gap: 5px;
            background: none;
            border: none;
            cursor: pointer;
            padding: 8px;
        }
        .hamburger span {
            display: block;
            width: 24px;
            height: 2px;
            background: var(--ink);
            border-radius: 4px;
            transition: all 0.3s;
        }
        .mobile-nav {
            display: none;
            background: var(--surface);
            border-top: 1px solid var(--line);
            padding: 16px 24px 24px;
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.4s;
        }
        .mobile-nav.open {
            display: block;
            max-height: 600px;
            overflow-y: auto;
        }
        .mobile-nav ul {
            list-style: none;
            margin: 0;
            padding: 0;
        }
        .mobile-nav ul li a,
        .mobile-nav ul li summary {
            display: block;
            padding: 12px 4px;
            font-size: 15px;
            font-weight: 500;
            color: var(--ink);
            border-bottom: 1px solid var(--line);
            cursor: pointer;
        }
        .mobile-nav ul li a:hover {
            color: var(--brand);
        }
        /* Buttons */
        .btn {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            padding: 12px 24px;
            border-radius: var(--radius-btn);
            font-weight: 600;
            font-size: 15px;
            border: 2px solid transparent;
            cursor: pointer;
            transition: all 0.2s;
            text-align: center;
        }
        .btn-primary {
            background: var(--brand);
            color: #fff;
        }
        .btn-primary:hover {
            background: var(--brand-hover);
        }
        .btn-outline {
            background: transparent;
            border-color: var(--brand);
            color: var(--brand);
        }
        .btn-outline:hover {
            background: var(--brand-light);
        }
        .btn:focus-visible {
            outline: 2px solid var(--brand);
            outline-offset: 2px;
        }
        /* Section */
        .section {
            padding: 80px 0;
        }
        .section-title {
            font-size: 32px;
            font-weight: 700;
            color: var(--ink);
            margin-bottom: 16px;
            line-height: 1.3;
        }
        .section-subtitle {
            font-size: 16px;
            color: var(--sub);
            max-width: 720px;
            margin-bottom: 40px;
            line-height: 1.7;
        }
        /* Category Header */
        .category-header {
            background: linear-gradient(180deg, #FFFFFF 0%, var(--bg) 100%);
            padding: 64px 0 40px;
        }
        .breadcrumb {
            display: flex;
            align-items: center;
            gap: 8px;
            font-size: 14px;
            color: var(--sub);
            margin-bottom: 16px;
            flex-wrap: wrap;
        }
        .breadcrumb a {
            color: var(--brand);
            transition: color 0.2s;
        }
        .breadcrumb a:hover {
            color: var(--brand-hover);
        }
        .breadcrumb .separator {
            color: var(--line);
        }
        .category-title {
            font-size: 40px;
            font-weight: 800;
            color: var(--ink);
            letter-spacing: -0.02em;
            margin-bottom: 12px;
            line-height: 1.2;
        }
        .category-desc {
            font-size: 16px;
            color: var(--sub);
            max-width: 720px;
            line-height: 1.7;
        }
        /* Metrics */
        .metric-card {
            background: var(--surface);
            border: 1px solid var(--line);
            border-radius: var(--radius-card);
            padding: 24px;
            box-shadow: var(--shadow-card);
            transition: all 0.2s;
        }
        .metric-card:hover {
            box-shadow: var(--shadow-card-hover);
            border-color: var(--brand);
        }
        .metric-value {
            font-size: 32px;
            font-weight: 800;
            color: var(--brand);
            line-height: 1;
        }
        .metric-value.copper {
            color: var(--copper);
        }
        .metric-label {
            font-size: 14px;
            color: var(--sub);
            margin-top: 8px;
        }
        .metric-tag {
            display: inline-block;
            background: var(--brand-light);
            color: var(--brand);
            padding: 2px 10px;
            border-radius: 999px;
            font-size: 12px;
            font-weight: 500;
            margin-top: 8px;
        }
        /* Resource Card */
        .resource-card {
            background: var(--surface);
            border: 1px solid var(--line);
            border-radius: var(--radius-card);
            overflow: hidden;
            box-shadow: var(--shadow-card);
            transition: all 0.3s;
            display: flex;
            flex-direction: column;
        }
        .resource-card:hover {
            transform: translateY(-4px);
            box-shadow: var(--shadow-card-hover);
            border-color: var(--brand);
        }
        .resource-cover {
            position: relative;
            aspect-ratio: 16/9;
            overflow: hidden;
            background: #E2E8F0;
        }
        .resource-cover img {
            width: 100%;
            height: 100%;
            object-fit: cover;
            transition: transform 0.5s;
        }
        .resource-card:hover .resource-cover img {
            transform: scale(1.03);
        }
        .resource-badge {
            position: absolute;
            top: 12px;
            left: 12px;
            background: var(--brand);
            color: #fff;
            padding: 4px 12px;
            border-radius: 999px;
            font-size: 12px;
            font-weight: 600;
        }
        .resource-body {
            padding: 20px;
            flex: 1;
            display: flex;
            flex-direction: column;
        }
        .resource-title {
            font-size: 19px;
            font-weight: 600;
            color: var(--ink);
            margin-bottom: 8px;
            line-height: 1.4;
        }
        .resource-meta {
            display: flex;
            align-items: center;
            gap: 12px;
            font-size: 13px;
            color: var(--sub);
            margin-bottom: 10px;
            flex-wrap: wrap;
        }
        .resource-tags {
            display: flex;
            flex-wrap: wrap;
            gap: 8px;
            margin-bottom: 10px;
        }
        .resource-tag {
            background: var(--brand-light);
            color: var(--brand);
            padding: 4px 10px;
            border-radius: 999px;
            font-size: 12px;
            font-weight: 500;
        }
        .resource-summary {
            font-size: 14px;
            color: var(--sub);
            line-height: 1.6;
            margin-top: auto;
        }
        /* Tags Cloud */
        .tags-cloud {
            display: flex;
            flex-wrap: wrap;
            gap: 12px;
        }
        .tag-btn {
            display: inline-flex;
            align-items: center;
            padding: 8px 16px;
            background: var(--surface);
            border: 1px solid var(--line);
            border-radius: 999px;
            font-size: 14px;
            font-weight: 500;
            color: var(--ink);
            transition: all 0.2s;
            cursor: pointer;
        }
        .tag-btn:hover {
            background: var(--brand-light);
            border-color: var(--brand);
            color: var(--brand);
        }
        /* Related Topics */
        .topic-card {
            background: var(--surface);
            border: 1px solid var(--line);
            border-radius: var(--radius-card);
            padding: 20px;
            box-shadow: var(--shadow-card);
            transition: all 0.2s;
            display: block;
            text-align: left;
        }
        .topic-card:hover {
            border-color: var(--brand);
            transform: translateY(-2px);
            box-shadow: var(--shadow-card-hover);
        }
        .topic-card-title {
            font-size: 16px;
            font-weight: 600;
            color: var(--ink);
            margin-bottom: 8px;
        }
        .topic-card-desc {
            font-size: 13px;
            color: var(--sub);
            line-height: 1.6;
        }
        /* FAQ */
        .faq-item {
            background: var(--surface);
            border: 1px solid var(--line);
            border-radius: 12px;
            margin-bottom: 12px;
            overflow: hidden;
        }
        .faq-item summary {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 16px 20px;
            font-size: 15px;
            font-weight: 600;
            cursor: pointer;
            list-style: none;
            color: var(--ink);
        }
        .faq-item summary::-webkit-details-marker {
            display: none;
        }
        .faq-item summary::after {
            content: "+";
            font-size: 20px;
            color: var(--sub);
            transition: transform 0.3s;
        }
        .faq-item[open] summary::after {
            transform: rotate(45deg);
        }
        .faq-content {
            padding: 0 20px 16px;
            font-size: 14px;
            color: var(--sub);
            line-height: 1.7;
        }
        /* Subscribe */
        .subscribe-form {
            background: var(--surface);
            border: 1px solid var(--line);
            border-radius: var(--radius-card);
            padding: 32px;
            box-shadow: var(--shadow-card);
        }
        .form-group {
            margin-bottom: 16px;
        }
        .form-label {
            display: block;
            font-size: 14px;
            font-weight: 500;
            margin-bottom: 8px;
            color: var(--ink);
        }
        .form-input {
            width: 100%;
            padding: 12px 16px;
            border: 1px solid var(--line);
            border-radius: 10px;
            background: var(--bg);
            font-size: 15px;
            transition: border-color 0.2s, box-shadow 0.2s;
            color: var(--ink);
        }
        .form-input:focus {
            border-color: var(--brand);
            box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
            outline: none;
        }
        /* Footer */
        .site-footer {
            background: var(--surface);
            border-top: 1px solid var(--line);
            padding: 64px 0 32px;
            margin-top: 80px;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 32px;
            margin-bottom: 40px;
        }
        .footer-brand {
            font-size: 18px;
            font-weight: 800;
            color: var(--ink);
            margin-bottom: 12px;
        }
        .footer-brand .logo-accent {
            color: var(--brand);
        }
        .footer-text {
            font-size: 14px;
            color: var(--sub);
            line-height: 1.7;
        }
        .footer-col-title {
            font-size: 14px;
            font-weight: 600;
            color: var(--ink);
            margin-bottom: 16px;
        }
        .footer-col ul {
            list-style: none;
            margin: 0;
            padding: 0;
        }
        .footer-col ul li {
            margin-bottom: 10px;
        }
        .footer-col ul li a {
            font-size: 14px;
            color: var(--sub);
            transition: color 0.2s;
        }
        .footer-col ul li a:hover {
            color: var(--brand);
        }
        .footer-bottom {
            display: flex;
            justify-content: space-between;
            align-items: center;
            border-top: 1px solid var(--line);
            padding-top: 24px;
            font-size: 13px;
            color: var(--sub);
            flex-wrap: wrap;
            gap: 8px;
        }
        /* Responsive */
        @media (max-width: 1024px) {
            .nav-desktop {
                display: none;
            }
            .hamburger {
                display: flex;
            }
            .mobile-nav {
                display: block;
            }
            .section {
                padding: 48px 0;
            }
            .category-title {
                font-size: 32px;
            }
            .section-title {
                font-size: 28px;
            }
        }
        @media (max-width: 768px) {
            .resource-grid {
                grid-template-columns: 1fr !important;
            }
            .topics-grid {
                grid-template-columns: 1fr !important;
            }
            .metrics-grid {
                grid-template-columns: 1fr 1fr !important;
            }
            .subscribe-grid {
                grid-template-columns: 1fr !important;
            }
        }
        @media (max-width: 520px) {
            .metrics-grid {
                grid-template-columns: 1fr !important;
            }
            .container {
                padding: 0 16px;
            }
            .logo-text {
                max-width: 200px;
                font-size: 16px;
            }
        }