/* roulang page: index */
/* ===== Design Variables ===== */
        :root {
            --color-primary: #1e40af;
            --color-primary-light: #2563eb;
            --color-primary-dark: #1e3a8a;
            --color-secondary: #f97316;
            --color-secondary-light: #fb923c;
            --color-secondary-dark: #ea580c;
            --color-accent: #0d9488;
            --color-bg: #ffffff;
            --color-bg-alt: #f8fafc;
            --color-bg-card: #ffffff;
            --color-bg-dark: #0f172a;
            --color-text: #1e293b;
            --color-text-light: #64748b;
            --color-text-muted: #94a3b8;
            --color-text-inverse: #f8fafc;
            --color-border: #e2e8f0;
            --color-border-light: #f1f5f9;
            --color-success: #10b981;
            --color-warning: #f59e0b;
            --color-error: #ef4444;
            --radius-sm: 6px;
            --radius-md: 12px;
            --radius-lg: 20px;
            --radius-xl: 28px;
            --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06), 0 1px 2px rgba(0, 0, 0, 0.04);
            --shadow-md: 0 4px 14px rgba(0, 0, 0, 0.08), 0 2px 6px rgba(0, 0, 0, 0.04);
            --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.10), 0 4px 12px rgba(0, 0, 0, 0.06);
            --shadow-xl: 0 24px 60px rgba(0, 0, 0, 0.14);
            --shadow-primary: 0 4px 20px rgba(30, 64, 175, 0.30);
            --shadow-secondary: 0 4px 20px rgba(249, 115, 22, 0.30);
            --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
            --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, 'Noto Sans SC', sans-serif;
            --spacing-section: 5rem;
            --spacing-block: 3rem;
            --max-width: 1200px;
            --header-height: 72px;
        }

        /* ===== Reset & Base ===== */
        *, *::before, *::after {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }
        html {
            scroll-behavior: smooth;
            -webkit-text-size-adjust: 100%;
        }
        body {
            font-family: var(--font-sans);
            font-size: 16px;
            line-height: 1.7;
            color: var(--color-text);
            background: var(--color-bg);
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
        }
        a {
            color: var(--color-primary);
            text-decoration: none;
            transition: color var(--transition);
        }
        a:hover {
            color: var(--color-primary-light);
        }
        a:focus-visible {
            outline: 3px solid var(--color-primary-light);
            outline-offset: 2px;
            border-radius: var(--radius-sm);
        }
        button, input, textarea, select {
            font-family: inherit;
            font-size: inherit;
            line-height: inherit;
        }
        button {
            cursor: pointer;
            border: none;
            background: none;
        }
        button:focus-visible {
            outline: 3px solid var(--color-primary-light);
            outline-offset: 2px;
        }
        ul, ol {
            list-style: none;
        }
        h1, h2, h3, h4, h5, h6 {
            line-height: 1.3;
            font-weight: 700;
            color: var(--color-text);
        }
        h1 { font-size: clamp(2rem, 5vw, 3.2rem); }
        h2 { font-size: clamp(1.6rem, 3.5vw, 2.4rem); }
        h3 { font-size: clamp(1.2rem, 2.5vw, 1.6rem); }
        h4 { font-size: 1.125rem; }
        p {
            margin-bottom: 1rem;
            color: var(--color-text-light);
        }
        p:last-child { margin-bottom: 0; }
        .container {
            width: 100%;
            max-width: var(--max-width);
            margin: 0 auto;
            padding: 0 1.5rem;
        }

        /* ===== Utility ===== */
        .section {
            padding: var(--spacing-section) 0;
        }
        .section-alt {
            background: var(--color-bg-alt);
        }
        .section-dark {
            background: var(--color-bg-dark);
            color: var(--color-text-inverse);
        }
        .section-dark h2,
        .section-dark h3,
        .section-dark .text-muted {
            color: var(--color-text-inverse);
        }
        .section-dark p {
            color: #cbd5e1;
        }
        .text-center { text-align: center; }
        .text-muted { color: var(--color-text-muted); }
        .mb-1 { margin-bottom: 0.5rem; }
        .mb-2 { margin-bottom: 1rem; }
        .mb-3 { margin-bottom: 1.5rem; }
        .mb-4 { margin-bottom: 2rem; }
        .mb-5 { margin-bottom: 3rem; }
        .mt-2 { margin-top: 1rem; }
        .mt-4 { margin-top: 2rem; }
        .gap-2 { gap: 0.75rem; }
        .gap-3 { gap: 1.25rem; }
        .gap-4 { gap: 2rem; }
        .flex-center {
            display: flex;
            align-items: center;
            justify-content: center;
        }
        .grid-2 {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 2rem;
        }
        .grid-3 {
            display: grid;
            grid-template-columns: 1fr 1fr 1fr;
            gap: 2rem;
        }
        .grid-4 {
            display: grid;
            grid-template-columns: 1fr 1fr 1fr 1fr;
            gap: 1.5rem;
        }

        /* ===== Section Title ===== */
        .section-header {
            text-align: center;
            max-width: 720px;
            margin: 0 auto var(--spacing-block);
        }
        .section-header h2 {
            margin-bottom: 0.75rem;
        }
        .section-header p {
            font-size: 1.1rem;
            color: var(--color-text-light);
        }
        .section-tag {
            display: inline-block;
            padding: 0.25rem 1rem;
            border-radius: 100px;
            background: rgba(30, 64, 175, 0.08);
            color: var(--color-primary);
            font-size: 0.85rem;
            font-weight: 600;
            letter-spacing: 0.02em;
            margin-bottom: 0.75rem;
        }
        .section-dark .section-tag {
            background: rgba(255, 255, 255, 0.12);
            color: var(--color-text-inverse);
        }

        /* ===== Buttons ===== */
        .btn {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 0.5rem;
            padding: 0.7rem 1.8rem;
            border-radius: var(--radius-md);
            font-weight: 600;
            font-size: 0.95rem;
            transition: all var(--transition);
            border: 2px solid transparent;
            text-align: center;
            line-height: 1.4;
        }
        .btn-primary {
            background: var(--color-primary);
            color: #fff;
            border-color: var(--color-primary);
            box-shadow: var(--shadow-primary);
        }
        .btn-primary:hover {
            background: var(--color-primary-dark);
            border-color: var(--color-primary-dark);
            color: #fff;
            transform: translateY(-2px);
            box-shadow: 0 8px 30px rgba(30, 64, 175, 0.35);
        }
        .btn-primary:active {
            transform: translateY(0);
            box-shadow: var(--shadow-sm);
        }
        .btn-secondary {
            background: var(--color-secondary);
            color: #fff;
            border-color: var(--color-secondary);
            box-shadow: var(--shadow-secondary);
        }
        .btn-secondary:hover {
            background: var(--color-secondary-dark);
            border-color: var(--color-secondary-dark);
            color: #fff;
            transform: translateY(-2px);
            box-shadow: 0 8px 30px rgba(249, 115, 22, 0.35);
        }
        .btn-secondary:active {
            transform: translateY(0);
        }
        .btn-outline {
            background: transparent;
            color: var(--color-primary);
            border-color: var(--color-primary);
        }
        .btn-outline:hover {
            background: var(--color-primary);
            color: #fff;
            transform: translateY(-2px);
        }
        .btn-light {
            background: #fff;
            color: var(--color-primary);
            border-color: #fff;
        }
        .btn-light:hover {
            background: var(--color-bg-alt);
            color: var(--color-primary-dark);
            transform: translateY(-2px);
        }
        .btn-lg {
            padding: 0.9rem 2.4rem;
            font-size: 1.05rem;
            border-radius: var(--radius-lg);
        }
        .btn-sm {
            padding: 0.4rem 1.2rem;
            font-size: 0.85rem;
            border-radius: var(--radius-sm);
        }
        .btn i {
            font-size: 0.9em;
        }

        /* ===== Header & Navigation ===== */
        .site-header {
            position: sticky;
            top: 0;
            z-index: 1000;
            background: rgba(255, 255, 255, 0.97);
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            border-bottom: 1px solid var(--color-border);
            height: var(--header-height);
            display: flex;
            align-items: center;
            transition: box-shadow var(--transition);
        }
        .site-header.scrolled {
            box-shadow: var(--shadow-md);
        }
        .header-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            width: 100%;
            max-width: var(--max-width);
            margin: 0 auto;
            padding: 0 1.5rem;
            position: relative;
        }
        .nav-left, .nav-right {
            display: flex;
            align-items: center;
            gap: 0.25rem;
            flex: 1;
        }
        .nav-left {
            justify-content: flex-start;
        }
        .nav-right {
            justify-content: flex-end;
        }
        .nav-logo {
            font-size: 1.4rem;
            font-weight: 800;
            color: var(--color-primary);
            letter-spacing: -0.02em;
            white-space: nowrap;
            padding: 0 1.2rem;
            flex-shrink: 0;
            transition: opacity var(--transition);
        }
        .nav-logo:hover {
            color: var(--color-primary);
            opacity: 0.85;
        }
        .nav-logo span {
            color: var(--color-secondary);
        }
        .nav-link {
            padding: 0.5rem 1rem;
            font-size: 0.92rem;
            font-weight: 500;
            color: var(--color-text-light);
            border-radius: var(--radius-sm);
            transition: all var(--transition);
            position: relative;
        }
        .nav-link:hover {
            color: var(--color-primary);
            background: rgba(30, 64, 175, 0.05);
        }
        .nav-link.active {
            color: var(--color-primary);
            background: rgba(30, 64, 175, 0.08);
            font-weight: 600;
        }
        .nav-link.active::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 1rem;
            right: 1rem;
            height: 2px;
            background: var(--color-primary);
            border-radius: 2px;
        }
        .mobile-toggle {
            display: none;
            font-size: 1.4rem;
            padding: 0.4rem 0.6rem;
            color: var(--color-text);
            border-radius: var(--radius-sm);
            transition: background var(--transition);
        }
        .mobile-toggle:hover {
            background: var(--color-bg-alt);
        }
        .mobile-menu {
            display: none;
            position: fixed;
            top: var(--header-height);
            left: 0;
            right: 0;
            background: rgba(255, 255, 255, 0.99);
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            border-bottom: 1px solid var(--color-border);
            padding: 1rem 1.5rem;
            box-shadow: var(--shadow-lg);
            z-index: 999;
            flex-direction: column;
            gap: 0.5rem;
        }
        .mobile-menu.open {
            display: flex;
        }
        .mobile-menu .nav-link {
            padding: 0.7rem 1rem;
            font-size: 1rem;
            border-radius: var(--radius-md);
        }
        .mobile-menu .nav-link.active {
            background: rgba(30, 64, 175, 0.10);
        }

        /* ===== Hero ===== */
        .hero {
            position: relative;
            min-height: 88vh;
            display: flex;
            align-items: center;
            justify-content: center;
            background: linear-gradient(135deg, rgba(15, 23, 42, 0.88) 0%, rgba(30, 64, 175, 0.78) 100%), url('/assets/images/backpic/back-1.png') center center / cover no-repeat;
            color: var(--color-text-inverse);
            overflow: hidden;
        }
        .hero::before {
            content: '';
            position: absolute;
            top: 0; left: 0; right: 0; bottom: 0;
            background: radial-gradient(ellipse at 20% 50%, rgba(249, 115, 22, 0.18) 0%, transparent 60%);
            pointer-events: none;
        }
        .hero-content {
            position: relative;
            z-index: 2;
            text-align: center;
            max-width: 800px;
            padding: 2rem 1.5rem;
        }
        .hero-badge {
            display: inline-block;
            padding: 0.35rem 1.4rem;
            border-radius: 100px;
            background: rgba(255, 255, 255, 0.12);
            border: 1px solid rgba(255, 255, 255, 0.18);
            font-size: 0.85rem;
            font-weight: 500;
            color: rgba(255, 255, 255, 0.9);
            margin-bottom: 1.2rem;
            backdrop-filter: blur(4px);
            letter-spacing: 0.03em;
        }
        .hero h1 {
            font-size: clamp(2.2rem, 6vw, 3.8rem);
            font-weight: 800;
            color: #fff;
            margin-bottom: 1.2rem;
            letter-spacing: -0.02em;
            line-height: 1.15;
        }
        .hero h1 span {
            color: var(--color-secondary);
            position: relative;
        }
        .hero p {
            font-size: clamp(1rem, 2vw, 1.25rem);
            color: rgba(255, 255, 255, 0.8);
            max-width: 600px;
            margin: 0 auto 2rem;
            line-height: 1.7;
        }
        .hero-actions {
            display: flex;
            flex-wrap: wrap;
            gap: 1rem;
            justify-content: center;
        }
        .hero-stats {
            display: flex;
            flex-wrap: wrap;
            gap: 2.5rem 3.5rem;
            justify-content: center;
            margin-top: 3rem;
            padding-top: 2.5rem;
            border-top: 1px solid rgba(255, 255, 255, 0.12);
        }
        .hero-stat-item {
            text-align: center;
        }
        .hero-stat-item .num {
            font-size: 2rem;
            font-weight: 800;
            color: #fff;
            line-height: 1.2;
        }
        .hero-stat-item .num span {
            color: var(--color-secondary);
        }
        .hero-stat-item .label {
            font-size: 0.85rem;
            color: rgba(255, 255, 255, 0.65);
            margin-top: 0.2rem;
        }

        /* ===== Intro Section ===== */
        .intro-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 3rem;
            align-items: center;
        }
        .intro-image {
            border-radius: var(--radius-lg);
            overflow: hidden;
            box-shadow: var(--shadow-lg);
            position: relative;
        }
        .intro-image img {
            width: 100%;
            height: 400px;
            object-fit: cover;
            transition: transform 0.6s ease;
        }
        .intro-image:hover img {
            transform: scale(1.03);
        }
        .intro-text h2 {
            margin-bottom: 1rem;
        }
        .intro-text p {
            margin-bottom: 1.2rem;
        }
        .intro-features {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 1rem;
            margin-top: 1.5rem;
        }
        .intro-feature-item {
            display: flex;
            align-items: flex-start;
            gap: 0.75rem;
            padding: 0.75rem 1rem;
            background: var(--color-bg-alt);
            border-radius: var(--radius-md);
            transition: background var(--transition);
        }
        .intro-feature-item:hover {
            background: rgba(30, 64, 175, 0.06);
        }
        .intro-feature-item i {
            color: var(--color-primary);
            font-size: 1.1rem;
            margin-top: 0.15rem;
            flex-shrink: 0;
        }
        .intro-feature-item span {
            font-size: 0.92rem;
            font-weight: 500;
            color: var(--color-text);
        }

        /* ===== Category Cards ===== */
        .category-cards {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
            gap: 1.8rem;
        }
        .category-card {
            background: var(--color-bg-card);
            border-radius: var(--radius-lg);
            overflow: hidden;
            box-shadow: var(--shadow-sm);
            border: 1px solid var(--color-border);
            transition: all var(--transition);
            display: flex;
            flex-direction: column;
        }
        .category-card:hover {
            transform: translateY(-6px);
            box-shadow: var(--shadow-lg);
            border-color: transparent;
        }
        .category-card .card-img {
            height: 200px;
            overflow: hidden;
            position: relative;
        }
        .category-card .card-img img {
            width: 100%;
            height: 100%;
            object-fit: cover;
            transition: transform 0.6s ease;
        }
        .category-card:hover .card-img img {
            transform: scale(1.06);
        }
        .category-card .card-img .overlay {
            position: absolute;
            top: 0; left: 0; right: 0; bottom: 0;
            background: linear-gradient(to top, rgba(15, 23, 42, 0.5), transparent);
        }
        .category-card .card-body {
            padding: 1.5rem;
            flex: 1;
            display: flex;
            flex-direction: column;
        }
        .category-card .card-body h3 {
            margin-bottom: 0.5rem;
            font-size: 1.2rem;
        }
        .category-card .card-body p {
            font-size: 0.92rem;
            color: var(--color-text-light);
            margin-bottom: 1rem;
            flex: 1;
        }
        .category-card .card-footer {
            padding: 0 1.5rem 1.5rem;
            display: flex;
            align-items: center;
            justify-content: space-between;
        }
        .category-card .badge {
            padding: 0.2rem 0.8rem;
            border-radius: 100px;
            font-size: 0.78rem;
            font-weight: 600;
            background: rgba(30, 64, 175, 0.08);
            color: var(--color-primary);
        }

        /* ===== Latest Posts ===== */
        .posts-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
            gap: 1.5rem;
        }
        .post-card {
            background: var(--color-bg-card);
            border-radius: var(--radius-md);
            padding: 1.5rem;
            border: 1px solid var(--color-border);
            transition: all var(--transition);
            display: flex;
            flex-direction: column;
        }
        .post-card:hover {
            box-shadow: var(--shadow-md);
            border-color: transparent;
            transform: translateY(-3px);
        }
        .post-card .post-category {
            display: inline-block;
            padding: 0.15rem 0.7rem;
            border-radius: 100px;
            font-size: 0.75rem;
            font-weight: 600;
            background: rgba(249, 115, 22, 0.10);
            color: var(--color-secondary);
            margin-bottom: 0.6rem;
            align-self: flex-start;
        }
        .post-card h3 {
            font-size: 1.05rem;
            margin-bottom: 0.5rem;
            line-height: 1.4;
        }
        .post-card h3 a {
            color: var(--color-text);
            transition: color var(--transition);
        }
        .post-card h3 a:hover {
            color: var(--color-primary);
        }
        .post-card p {
            font-size: 0.9rem;
            color: var(--color-text-light);
            margin-bottom: 0.8rem;
            flex: 1;
            display: -webkit-box;
            -webkit-line-clamp: 2;
            -webkit-box-orient: vertical;
            overflow: hidden;
        }
        .post-card .post-meta {
            display: flex;
            align-items: center;
            justify-content: space-between;
            font-size: 0.82rem;
            color: var(--color-text-muted);
            padding-top: 0.75rem;
            border-top: 1px solid var(--color-border-light);
        }
        .post-card .post-meta i {
            margin-right: 0.3rem;
        }
        .empty-posts {
            grid-column: 1 / -1;
            text-align: center;
            padding: 3rem 1rem;
            color: var(--color-text-muted);
            background: var(--color-bg-alt);
            border-radius: var(--radius-md);
            font-size: 1rem;
        }

        /* ===== Stats / Data Section ===== */
        .stats-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
            gap: 1.5rem;
        }
        .stat-card {
            background: var(--color-bg-card);
            border-radius: var(--radius-lg);
            padding: 2rem 1.5rem;
            text-align: center;
            border: 1px solid var(--color-border);
            transition: all var(--transition);
        }
        .stat-card:hover {
            transform: translateY(-4px);
            box-shadow: var(--shadow-md);
        }
        .stat-card .stat-icon {
            font-size: 2rem;
            color: var(--color-primary);
            margin-bottom: 0.75rem;
        }
        .stat-card .stat-number {
            font-size: 2.2rem;
            font-weight: 800;
            color: var(--color-text);
            line-height: 1.2;
        }
        .stat-card .stat-number span {
            color: var(--color-secondary);
        }
        .stat-card .stat-label {
            font-size: 0.9rem;
            color: var(--color-text-light);
            margin-top: 0.3rem;
        }

        /* ===== Features ===== */
        .features-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
            gap: 1.8rem;
        }
        .feature-card {
            background: var(--color-bg-card);
            border-radius: var(--radius-lg);
            padding: 2rem 1.5rem;
            border: 1px solid var(--color-border);
            transition: all var(--transition);
            text-align: center;
        }
        .feature-card:hover {
            transform: translateY(-5px);
            box-shadow: var(--shadow-lg);
            border-color: transparent;
        }
        .feature-card .feature-icon {
            width: 60px;
            height: 60px;
            border-radius: var(--radius-md);
            background: rgba(30, 64, 175, 0.08);
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0 auto 1rem;
            font-size: 1.5rem;
            color: var(--color-primary);
            transition: all var(--transition);
        }
        .feature-card:hover .feature-icon {
            background: var(--color-primary);
            color: #fff;
        }
        .feature-card h3 {
            font-size: 1.1rem;
            margin-bottom: 0.5rem;
        }
        .feature-card p {
            font-size: 0.9rem;
            color: var(--color-text-light);
        }

        /* ===== FAQ ===== */
        .faq-list {
            max-width: 780px;
            margin: 0 auto;
            display: flex;
            flex-direction: column;
            gap: 0.75rem;
        }
        .faq-item {
            background: var(--color-bg-card);
            border: 1px solid var(--color-border);
            border-radius: var(--radius-md);
            overflow: hidden;
            transition: all var(--transition);
        }
        .faq-item:hover {
            border-color: var(--color-primary-light);
        }
        .faq-item.open {
            border-color: var(--color-primary);
            box-shadow: var(--shadow-sm);
        }
        .faq-question {
            width: 100%;
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 1.2rem 1.5rem;
            font-size: 1rem;
            font-weight: 600;
            color: var(--color-text);
            text-align: left;
            background: none;
            transition: color var(--transition);
        }
        .faq-question:hover {
            color: var(--color-primary);
        }
        .faq-question i {
            font-size: 0.85rem;
            color: var(--color-text-muted);
            transition: transform var(--transition);
            flex-shrink: 0;
            margin-left: 1rem;
        }
        .faq-item.open .faq-question i {
            transform: rotate(180deg);
            color: var(--color-primary);
        }
        .faq-answer {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.35s ease, padding 0.35s ease;
            padding: 0 1.5rem;
        }
        .faq-item.open .faq-answer {
            max-height: 300px;
            padding: 0 1.5rem 1.2rem;
        }
        .faq-answer p {
            font-size: 0.95rem;
            color: var(--color-text-light);
            margin: 0;
        }

        /* ===== CTA ===== */
        .cta-section {
            background: linear-gradient(135deg, var(--color-primary-dark) 0%, var(--color-primary) 50%, var(--color-primary-light) 100%);
            padding: 4rem 0;
            text-align: center;
            color: #fff;
            position: relative;
            overflow: hidden;
        }
        .cta-section::before {
            content: '';
            position: absolute;
            top: 0; left: 0; right: 0; bottom: 0;
            background: radial-gradient(ellipse at 80% 30%, rgba(249, 115, 22, 0.15) 0%, transparent 60%);
            pointer-events: none;
        }
        .cta-section .container {
            position: relative;
            z-index: 2;
        }
        .cta-section h2 {
            color: #fff;
            font-size: clamp(1.6rem, 3vw, 2.4rem);
            margin-bottom: 0.75rem;
        }
        .cta-section p {
            color: rgba(255, 255, 255, 0.8);
            max-width: 600px;
            margin: 0 auto 1.8rem;
            font-size: 1.05rem;
        }
        .cta-section .btn-light {
            box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
        }
        .cta-section .btn-light:hover {
            box-shadow: 0 8px 30px rgba(0, 0, 0, 0.25);
        }

        /* ===== Footer ===== */
        .site-footer {
            background: var(--color-bg-dark);
            color: var(--color-text-inverse);
            padding: 3.5rem 0 0;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr 1fr;
            gap: 2.5rem;
            padding-bottom: 2.5rem;
            border-bottom: 1px solid rgba(255, 255, 255, 0.08);
        }
        .footer-brand .nav-logo {
            padding: 0;
            margin-bottom: 0.75rem;
            display: inline-block;
            color: #fff;
        }
        .footer-brand .nav-logo span {
            color: var(--color-secondary);
        }
        .footer-brand p {
            font-size: 0.9rem;
            color: #94a3b8;
            max-width: 300px;
        }
        .footer-col h4 {
            color: #fff;
            font-size: 0.95rem;
            margin-bottom: 1rem;
            font-weight: 600;
        }
        .footer-col ul li {
            margin-bottom: 0.45rem;
        }
        .footer-col ul li a {
            color: #94a3b8;
            font-size: 0.88rem;
            transition: color var(--transition);
        }
        .footer-col ul li a:hover {
            color: var(--color-secondary);
        }
        .footer-bottom {
            padding: 1.5rem 0;
            display: flex;
            flex-wrap: wrap;
            align-items: center;
            justify-content: space-between;
            font-size: 0.85rem;
            color: #64748b;
        }
        .footer-bottom a {
            color: #94a3b8;
        }
        .footer-bottom a:hover {
            color: var(--color-secondary);
        }
        .footer-bottom .social-links {
            display: flex;
            gap: 1rem;
        }
        .footer-bottom .social-links a {
            display: flex;
            align-items: center;
            justify-content: center;
            width: 36px;
            height: 36px;
            border-radius: 50%;
            background: rgba(255, 255, 255, 0.06);
            color: #94a3b8;
            font-size: 0.95rem;
            transition: all var(--transition);
        }
        .footer-bottom .social-links a:hover {
            background: var(--color-secondary);
            color: #fff;
            transform: translateY(-2px);
        }

        /* ===== Responsive ===== */
        @media (max-width: 1024px) {
            :root {
                --spacing-section: 3.5rem;
                --spacing-block: 2rem;
            }
            .footer-grid {
                grid-template-columns: 1fr 1fr;
            }
            .intro-grid {
                gap: 2rem;
            }
        }

        @media (max-width: 768px) {
            :root {
                --spacing-section: 2.8rem;
                --header-height: 64px;
            }
            .nav-left, .nav-right {
                display: none;
            }
            .mobile-toggle {
                display: block;
            }
            .header-inner {
                justify-content: space-between;
            }
            .nav-logo {
                font-size: 1.2rem;
                padding: 0;
                position: absolute;
                left: 50%;
                transform: translateX(-50%);
            }
            .intro-grid {
                grid-template-columns: 1fr;
            }
            .intro-image img {
                height: 260px;
            }
            .intro-features {
                grid-template-columns: 1fr;
            }
            .grid-2, .grid-3, .grid-4 {
                grid-template-columns: 1fr;
            }
            .hero {
                min-height: 70vh;
            }
            .hero-stats {
                gap: 1.5rem 2rem;
            }
            .hero-stat-item .num {
                font-size: 1.5rem;
            }
            .posts-grid {
                grid-template-columns: 1fr;
            }
            .category-cards {
                grid-template-columns: 1fr;
            }
            .stats-grid {
                grid-template-columns: 1fr 1fr;
            }
            .features-grid {
                grid-template-columns: 1fr 1fr;
            }
            .footer-grid {
                grid-template-columns: 1fr;
                gap: 1.5rem;
            }
            .footer-bottom {
                flex-direction: column;
                gap: 1rem;
                text-align: center;
            }
            .faq-question {
                font-size: 0.92rem;
                padding: 1rem 1.2rem;
            }
            .faq-answer {
                padding: 0 1.2rem;
            }
            .faq-item.open .faq-answer {
                padding: 0 1.2rem 1rem;
            }
            .section-header p {
                font-size: 0.95rem;
            }
        }

        @media (max-width: 520px) {
            .hero h1 {
                font-size: 1.8rem;
            }
            .hero p {
                font-size: 0.95rem;
            }
            .hero-actions {
                flex-direction: column;
                align-items: center;
            }
            .hero-actions .btn {
                width: 100%;
                max-width: 280px;
            }
            .stats-grid {
                grid-template-columns: 1fr 1fr;
                gap: 1rem;
            }
            .stat-card {
                padding: 1.2rem 0.8rem;
            }
            .stat-card .stat-number {
                font-size: 1.6rem;
            }
            .features-grid {
                grid-template-columns: 1fr;
            }
            .post-card {
                padding: 1.2rem;
            }
            .category-card .card-img {
                height: 160px;
            }
            .container {
                padding: 0 1rem;
            }
            .nav-logo {
                font-size: 1.05rem;
            }
            .section-tag {
                font-size: 0.75rem;
            }
        }

        /* ===== Animations ===== */
        @keyframes fadeUp {
            from { opacity: 0; transform: translateY(30px); }
            to { opacity: 1; transform: translateY(0); }
        }
        .animate-fade-up {
            animation: fadeUp 0.6s ease forwards;
        }
        .delay-1 { animation-delay: 0.1s; }
        .delay-2 { animation-delay: 0.2s; }
        .delay-3 { animation-delay: 0.3s; }
        .delay-4 { animation-delay: 0.4s; }

/* roulang page: article */
/* ===== Design Variables ===== */
    :root {
        --primary: #1a3a5c;
        --primary-dark: #0f2a44;
        --primary-light: #2c5a8c;
        --secondary: #e8b830;
        --secondary-light: #f0d060;
        --secondary-dark: #c9a020;
        --accent: #f0a030;
        --bg: #f5f7fa;
        --bg-white: #ffffff;
        --bg-card: #ffffff;
        --bg-dark: #0f1a2e;
        --text: #1a1a2e;
        --text-light: #6b7280;
        --text-white: #f8f9fa;
        --border: #e2e6ef;
        --radius: 12px;
        --radius-sm: 8px;
        --radius-lg: 20px;
        --shadow: 0 4px 20px rgba(26, 58, 92, 0.08);
        --shadow-hover: 0 12px 40px rgba(26, 58, 92, 0.16);
        --shadow-btn: 0 4px 14px rgba(232, 184, 48, 0.35);
        --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
        --container: 1200px;
        --content-width: 780px;
        --spacing-section: 4.5rem;
        --spacing-block: 2.5rem;
    }

    /* ===== Reset & Base ===== */
    *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
    html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
    body {
        font-family: var(--font);
        font-size: 16px;
        line-height: 1.7;
        color: var(--text);
        background: var(--bg);
        -webkit-font-smoothing: antialiased;
        -moz-osx-font-smoothing: grayscale;
    }
    a { color: var(--primary); text-decoration: none; transition: color var(--transition); }
    a:hover, a:focus-visible { color: var(--secondary); }
    a:focus-visible { outline: 2px solid var(--secondary); outline-offset: 2px; border-radius: 4px; }
    img { max-width: 100%; height: auto; display: block; }
    button, input, textarea { font-family: inherit; font-size: inherit; }
    button { cursor: pointer; border: none; background: none; }
    ul, ol { list-style: none; }
    h1, h2, h3, h4, h5, h6 { line-height: 1.3; color: var(--primary); font-weight: 700; }
    h1 { font-size: 2.4rem; }
    h2 { font-size: 2rem; }
    h3 { font-size: 1.4rem; }
    h4 { font-size: 1.15rem; }
    p { margin-bottom: 1rem; color: var(--text); }
    .container { max-width: var(--container); margin: 0 auto; padding: 0 1.5rem; }
    .content-container { max-width: var(--content-width); margin: 0 auto; padding: 0 1.5rem; }
    .section { padding: var(--spacing-section) 0; }
    .section-title { text-align: center; margin-bottom: 2.5rem; }
    .section-title h2 { font-size: 2rem; position: relative; display: inline-block; }
    .section-title h2::after { content: ''; display: block; width: 60px; height: 4px; background: var(--secondary); border-radius: 4px; margin: 0.6rem auto 0; }
    .section-title p { color: var(--text-light); font-size: 1.05rem; margin-top: 0.6rem; }

    /* ===== Header / Nav ===== */
    .site-header {
        background: var(--bg-white);
        border-bottom: 1px solid var(--border);
        position: sticky;
        top: 0;
        z-index: 1000;
        box-shadow: 0 2px 12px rgba(26, 58, 92, 0.05);
    }
    .header-inner {
        max-width: var(--container);
        margin: 0 auto;
        padding: 0 1.5rem;
        display: flex;
        align-items: center;
        justify-content: space-between;
        height: 68px;
        position: relative;
    }
    .nav-left, .nav-right {
        display: flex;
        align-items: center;
        gap: 0.25rem;
    }
    .nav-link {
        padding: 0.5rem 1rem;
        font-size: 0.95rem;
        font-weight: 500;
        color: var(--text-light);
        border-radius: var(--radius-sm);
        transition: all var(--transition);
        position: relative;
    }
    .nav-link:hover { color: var(--primary); background: rgba(26, 58, 92, 0.04); }
    .nav-link.active { color: var(--primary); background: rgba(26, 58, 92, 0.06); font-weight: 600; }
    .nav-link.active::after { content: ''; position: absolute; bottom: 0; left: 50%; transform: translateX(-50%); width: 20px; height: 3px; background: var(--secondary); border-radius: 4px; }
    .nav-logo {
        font-size: 1.5rem;
        font-weight: 800;
        color: var(--primary);
        letter-spacing: 1px;
        display: flex;
        align-items: center;
        gap: 0.1rem;
        text-decoration: none;
        flex-shrink: 0;
        margin: 0 1rem;
    }
    .nav-logo span { color: var(--secondary); font-weight: 800; }
    .nav-logo:hover { color: var(--primary); }
    .mobile-toggle { display: none; background: none; border: none; font-size: 1.5rem; color: var(--primary); padding: 0.4rem; border-radius: var(--radius-sm); }
    .mobile-toggle:hover { background: rgba(26, 58, 92, 0.06); }
    .mobile-menu {
        display: none;
        flex-direction: column;
        padding: 0.5rem 1.5rem 1rem;
        background: var(--bg-white);
        border-top: 1px solid var(--border);
        gap: 0.25rem;
    }
    .mobile-menu.open { display: flex; }
    .mobile-menu .nav-link { padding: 0.7rem 1rem; }

    /* ===== Hero / Banner ===== */
    .article-banner {
        position: relative;
        background: var(--primary-dark);
        background-image: url('/assets/images/backpic/back-1.png');
        background-size: cover;
        background-position: center;
        background-repeat: no-repeat;
        padding: 5rem 0 3.5rem;
        color: var(--text-white);
        min-height: 320px;
        display: flex;
        align-items: center;
    }
    .article-banner::before {
        content: '';
        position: absolute;
        inset: 0;
        background: linear-gradient(135deg, rgba(15, 42, 68, 0.85) 0%, rgba(26, 58, 92, 0.7) 100%);
        z-index: 1;
    }
    .article-banner .content-container { position: relative; z-index: 2; width: 100%; }
    .article-banner h1 {
        color: var(--text-white);
        font-size: 2.4rem;
        font-weight: 800;
        line-height: 1.3;
        margin-bottom: 0.8rem;
        max-width: 780px;
    }
    .article-banner .meta {
        display: flex;
        flex-wrap: wrap;
        align-items: center;
        gap: 1rem 1.5rem;
        font-size: 0.95rem;
        color: rgba(255,255,255,0.85);
    }
    .article-banner .meta .tag {
        display: inline-block;
        background: var(--secondary);
        color: var(--primary-dark);
        padding: 0.2rem 0.9rem;
        border-radius: 20px;
        font-weight: 600;
        font-size: 0.85rem;
    }
    .article-banner .meta i { margin-right: 0.35rem; opacity: 0.8; }

    /* ===== Article Body ===== */
    .article-body {
        background: var(--bg-white);
        border-radius: var(--radius);
        box-shadow: var(--shadow);
        padding: 2.5rem 2.8rem;
        margin-top: -2rem;
        position: relative;
        z-index: 3;
    }
    .article-body .article-content {
        font-size: 1.05rem;
        line-height: 1.85;
        color: var(--text);
    }
    .article-body .article-content h2,
    .article-body .article-content h3,
    .article-body .article-content h4 {
        margin-top: 1.8rem;
        margin-bottom: 0.8rem;
        color: var(--primary);
    }
    .article-body .article-content p {
        margin-bottom: 1.2rem;
    }
    .article-body .article-content ul,
    .article-body .article-content ol {
        margin: 0.8rem 0 1.2rem 1.5rem;
    }
    .article-body .article-content li {
        margin-bottom: 0.4rem;
        list-style: disc;
    }
    .article-body .article-content blockquote {
        border-left: 4px solid var(--secondary);
        padding: 0.8rem 1.2rem;
        margin: 1.2rem 0;
        background: rgba(232, 184, 48, 0.06);
        border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
        color: var(--text-light);
        font-style: italic;
    }
    .article-body .article-content img {
        border-radius: var(--radius-sm);
        margin: 1.5rem 0;
        box-shadow: var(--shadow);
    }
    .article-body .article-content a {
        color: var(--primary-light);
        text-decoration: underline;
        text-underline-offset: 2px;
    }
    .article-body .article-content a:hover { color: var(--secondary); }
    .article-footer-meta {
        display: flex;
        flex-wrap: wrap;
        align-items: center;
        justify-content: space-between;
        padding-top: 1.5rem;
        margin-top: 2rem;
        border-top: 1px solid var(--border);
        font-size: 0.9rem;
        color: var(--text-light);
    }
    .article-footer-meta .share-links a {
        display: inline-flex;
        align-items: center;
        justify-content: center;
        width: 36px;
        height: 36px;
        border-radius: 50%;
        background: var(--bg);
        color: var(--text-light);
        margin-left: 0.4rem;
        transition: all var(--transition);
    }
    .article-footer-meta .share-links a:hover {
        background: var(--secondary);
        color: var(--primary-dark);
        transform: translateY(-2px);
    }

    /* ===== Not Found ===== */
    .not-found-section {
        min-height: 60vh;
        display: flex;
        align-items: center;
        justify-content: center;
        text-align: center;
        padding: 4rem 1.5rem;
    }
    .not-found-section .not-found-card {
        background: var(--bg-white);
        border-radius: var(--radius-lg);
        padding: 3.5rem 2.5rem;
        box-shadow: var(--shadow);
        max-width: 520px;
        width: 100%;
    }
    .not-found-section .not-found-card i {
        font-size: 3.5rem;
        color: var(--secondary);
        margin-bottom: 1.2rem;
    }
    .not-found-section .not-found-card h1 {
        font-size: 1.8rem;
        margin-bottom: 0.6rem;
    }
    .not-found-section .not-found-card p {
        color: var(--text-light);
        margin-bottom: 1.8rem;
    }

    /* ===== Related Posts ===== */
    .related-section {
        background: var(--bg);
    }
    .related-grid {
        display: grid;
        grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
        gap: 1.5rem;
    }
    .related-card {
        background: var(--bg-white);
        border-radius: var(--radius);
        overflow: hidden;
        box-shadow: var(--shadow);
        transition: all var(--transition);
        display: flex;
        flex-direction: column;
    }
    .related-card:hover {
        transform: translateY(-6px);
        box-shadow: var(--shadow-hover);
    }
    .related-card .card-img {
        height: 180px;
        background: var(--primary-light);
        background-size: cover;
        background-position: center;
        position: relative;
    }
    .related-card .card-img .tag {
        position: absolute;
        top: 0.8rem;
        left: 0.8rem;
        background: var(--secondary);
        color: var(--primary-dark);
        padding: 0.2rem 0.8rem;
        border-radius: 20px;
        font-size: 0.75rem;
        font-weight: 600;
    }
    .related-card .card-body {
        padding: 1.2rem 1.3rem 1.3rem;
        flex: 1;
        display: flex;
        flex-direction: column;
    }
    .related-card .card-body h3 {
        font-size: 1.05rem;
        font-weight: 600;
        color: var(--primary);
        margin-bottom: 0.3rem;
        line-height: 1.4;
        display: -webkit-box;
        -webkit-line-clamp: 2;
        -webkit-box-orient: vertical;
        overflow: hidden;
    }
    .related-card .card-body p {
        font-size: 0.9rem;
        color: var(--text-light);
        margin-bottom: 0.6rem;
        flex: 1;
        display: -webkit-box;
        -webkit-line-clamp: 2;
        -webkit-box-orient: vertical;
        overflow: hidden;
    }
    .related-card .card-body .meta-bottom {
        display: flex;
        align-items: center;
        justify-content: space-between;
        font-size: 0.8rem;
        color: var(--text-light);
    }
    .related-card .card-body .meta-bottom i { margin-right: 0.25rem; }

    /* ===== CTA ===== */
    .cta-section {
        background: var(--primary-dark);
        background-image: url('/assets/images/backpic/back-3.png');
        background-size: cover;
        background-position: center;
        position: relative;
        padding: 4.5rem 0;
    }
    .cta-section::before {
        content: '';
        position: absolute;
        inset: 0;
        background: linear-gradient(135deg, rgba(15, 42, 68, 0.88) 0%, rgba(26, 58, 92, 0.78) 100%);
        z-index: 1;
    }
    .cta-section .container { position: relative; z-index: 2; text-align: center; }
    .cta-section h2 { color: var(--text-white); font-size: 1.8rem; margin-bottom: 0.6rem; }
    .cta-section p { color: rgba(255,255,255,0.8); max-width: 600px; margin: 0 auto 1.8rem; font-size: 1.05rem; }
    .cta-btn {
        display: inline-flex;
        align-items: center;
        gap: 0.5rem;
        background: var(--secondary);
        color: var(--primary-dark);
        padding: 0.85rem 2.2rem;
        font-size: 1.05rem;
        font-weight: 700;
        border-radius: 50px;
        box-shadow: var(--shadow-btn);
        transition: all var(--transition);
        border: none;
    }
    .cta-btn:hover {
        background: var(--secondary-light);
        transform: translateY(-3px);
        box-shadow: 0 8px 24px rgba(232, 184, 48, 0.45);
        color: var(--primary-dark);
    }
    .cta-btn:focus-visible { outline: 2px solid var(--text-white); outline-offset: 4px; }

    /* ===== Footer ===== */
    .site-footer {
        background: var(--bg-dark);
        color: rgba(255,255,255,0.7);
        padding: 3.5rem 0 0;
    }
    .footer-grid {
        display: grid;
        grid-template-columns: 1.6fr 1fr 1fr 1.2fr;
        gap: 2.5rem;
        padding-bottom: 2.5rem;
        border-bottom: 1px solid rgba(255,255,255,0.08);
    }
    .footer-brand .nav-logo { font-size: 1.5rem; color: var(--text-white); margin: 0 0 0.8rem 0; }
    .footer-brand p { font-size: 0.9rem; color: rgba(255,255,255,0.55); line-height: 1.7; max-width: 320px; }
    .footer-col h4 { color: var(--text-white); font-size: 1rem; font-weight: 600; margin-bottom: 1rem; }
    .footer-col ul li { margin-bottom: 0.6rem; }
    .footer-col ul li a { color: rgba(255,255,255,0.55); font-size: 0.9rem; transition: all var(--transition); }
    .footer-col ul li a:hover { color: var(--secondary); padding-left: 4px; }
    .footer-bottom {
        display: flex;
        align-items: center;
        justify-content: space-between;
        padding: 1.5rem 0;
        font-size: 0.85rem;
        color: rgba(255,255,255,0.4);
        flex-wrap: wrap;
        gap: 0.8rem;
    }
    .social-links { display: flex; gap: 0.8rem; }
    .social-links a {
        display: inline-flex;
        align-items: center;
        justify-content: center;
        width: 36px;
        height: 36px;
        border-radius: 50%;
        background: rgba(255,255,255,0.06);
        color: rgba(255,255,255,0.5);
        font-size: 1rem;
        transition: all var(--transition);
    }
    .social-links a:hover { background: var(--secondary); color: var(--primary-dark); transform: translateY(-2px); }

    /* ===== Button Global ===== */
    .btn {
        display: inline-flex;
        align-items: center;
        gap: 0.5rem;
        padding: 0.7rem 1.5rem;
        border-radius: 50px;
        font-weight: 600;
        font-size: 0.95rem;
        transition: all var(--transition);
        border: none;
        cursor: pointer;
    }
    .btn-primary { background: var(--secondary); color: var(--primary-dark); box-shadow: var(--shadow-btn); }
    .btn-primary:hover { background: var(--secondary-light); transform: translateY(-2px); box-shadow: 0 8px 24px rgba(232, 184, 48, 0.4); color: var(--primary-dark); }
    .btn-outline { background: transparent; border: 2px solid var(--secondary); color: var(--secondary); }
    .btn-outline:hover { background: var(--secondary); color: var(--primary-dark); transform: translateY(-2px); }
    .btn-sm { padding: 0.4rem 1rem; font-size: 0.85rem; }

    /* ===== Responsive ===== */
    @media (max-width: 1024px) {
        .footer-grid { grid-template-columns: 1fr 1fr; }
        .article-banner h1 { font-size: 2rem; }
    }
    @media (max-width: 768px) {
        .nav-left, .nav-right { display: none; }
        .mobile-toggle { display: block; }
        .header-inner { justify-content: space-between; }
        .nav-logo { margin: 0; font-size: 1.3rem; }
        .article-banner { padding: 3.5rem 0 2.5rem; min-height: 240px; }
        .article-banner h1 { font-size: 1.6rem; }
        .article-body { padding: 1.5rem 1.2rem; margin-top: -1.5rem; }
        .article-body .article-content { font-size: 1rem; }
        .related-grid { grid-template-columns: 1fr 1fr; }
        .footer-grid { grid-template-columns: 1fr; gap: 1.8rem; }
        .footer-bottom { flex-direction: column; text-align: center; }
        .section-title h2 { font-size: 1.6rem; }
        .cta-section h2 { font-size: 1.4rem; }
        :root { --spacing-section: 3rem; }
    }
    @media (max-width: 520px) {
        .related-grid { grid-template-columns: 1fr; }
        .article-banner h1 { font-size: 1.35rem; }
        .article-banner .meta { font-size: 0.85rem; gap: 0.6rem; }
        .article-body { padding: 1.2rem 0.8rem; }
        .article-footer-meta { flex-direction: column; gap: 0.8rem; align-items: flex-start; }
        .nav-logo { font-size: 1.1rem; }
        .not-found-section .not-found-card { padding: 2rem 1.2rem; }
        .cta-btn { padding: 0.7rem 1.6rem; font-size: 0.95rem; }
    }

    /* ===== Utility ===== */
    .text-center { text-align: center; }
    .mb-1 { margin-bottom: 0.5rem; }
    .mb-2 { margin-bottom: 1rem; }
    .mb-3 { margin-bottom: 1.5rem; }
    .mt-2 { margin-top: 1rem; }
    .mt-3 { margin-top: 1.5rem; }
    .gap-1 { gap: 0.5rem; }
    .flex-center { display: flex; align-items: center; justify-content: center; }
    .flex-wrap { flex-wrap: wrap; }
    .sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0; }

/* roulang page: category1 */
/* ===== :root Design Variables ===== */
        :root {
            --primary: #1a56db;
            --primary-light: #3b82f6;
            --primary-dark: #1e40af;
            --primary-bg: #eff6ff;
            --secondary: #f59e0b;
            --secondary-light: #fbbf24;
            --secondary-dark: #d97706;
            --accent: #10b981;
            --accent-light: #34d399;
            --bg: #ffffff;
            --bg-alt: #f8fafc;
            --bg-card: #ffffff;
            --text: #0f172a;
            --text-light: #475569;
            --text-muted: #94a3b8;
            --border: #e2e8f0;
            --border-light: #f1f5f9;
            --radius: 12px;
            --radius-sm: 8px;
            --radius-lg: 20px;
            --shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
            --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.10);
            --shadow-hover: 0 16px 48px rgba(0, 0, 0, 0.12);
            --transition: 0.25s ease;
            --font: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
            --max-width: 1200px;
            --header-h: 72px;
        }

        /* ===== Reset & Base ===== */
        *,
        *::before,
        *::after {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }
        html {
            scroll-behavior: smooth;
            -webkit-text-size-adjust: 100%;
        }
        body {
            font-family: var(--font);
            font-size: 16px;
            line-height: 1.7;
            color: var(--text);
            background: var(--bg);
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
            padding-top: var(--header-h);
        }
        a {
            color: inherit;
            text-decoration: none;
            transition: color var(--transition);
        }
        a:hover {
            color: var(--primary);
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
            border-radius: var(--radius-sm);
        }
        button,
        input,
        select,
        textarea {
            font-family: inherit;
            font-size: inherit;
            line-height: inherit;
            border: none;
            outline: none;
        }
        button {
            cursor: pointer;
            background: none;
        }
        ul,
        ol {
            list-style: none;
        }
        h1,
        h2,
        h3,
        h4,
        h5,
        h6 {
            font-weight: 700;
            line-height: 1.25;
            color: var(--text);
        }
        h1 {
            font-size: 2.8rem;
        }
        h2 {
            font-size: 2.2rem;
            margin-bottom: 1rem;
        }
        h3 {
            font-size: 1.5rem;
            margin-bottom: 0.75rem;
        }
        h4 {
            font-size: 1.2rem;
            margin-bottom: 0.5rem;
        }
        p {
            color: var(--text-light);
            margin-bottom: 1rem;
        }
        .container {
            max-width: var(--max-width);
            margin: 0 auto;
            padding: 0 24px;
        }
        .section {
            padding: 80px 0;
        }
        .section-alt {
            background: var(--bg-alt);
        }
        .section-title {
            text-align: center;
            margin-bottom: 48px;
        }
        .section-title h2 {
            margin-bottom: 12px;
        }
        .section-title p {
            max-width: 640px;
            margin: 0 auto;
            font-size: 1.1rem;
            color: var(--text-muted);
        }
        .text-center {
            text-align: center;
        }

        /* ===== Buttons ===== */
        .btn {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 12px 28px;
            border-radius: var(--radius-sm);
            font-weight: 600;
            font-size: 1rem;
            transition: all var(--transition);
            border: 2px solid transparent;
            white-space: nowrap;
        }
        .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(26, 86, 219, 0.30);
        }
        .btn-secondary {
            background: var(--secondary);
            color: #fff;
            border-color: var(--secondary);
        }
        .btn-secondary:hover {
            background: var(--secondary-dark);
            border-color: var(--secondary-dark);
            color: #fff;
            transform: translateY(-2px);
            box-shadow: 0 8px 24px rgba(245, 158, 11, 0.30);
        }
        .btn-outline {
            background: transparent;
            color: var(--primary);
            border-color: var(--primary);
        }
        .btn-outline:hover {
            background: var(--primary);
            color: #fff;
            transform: translateY(-2px);
        }
        .btn-white {
            background: #fff;
            color: var(--primary);
            border-color: #fff;
        }
        .btn-white:hover {
            background: var(--bg-alt);
            transform: translateY(-2px);
            box-shadow: 0 8px 24px rgba(0, 0, 0, 0.12);
        }
        .btn-lg {
            padding: 16px 36px;
            font-size: 1.1rem;
        }
        .btn:focus-visible {
            outline: 3px solid var(--primary-light);
            outline-offset: 2px;
        }

        /* ===== Badge / Tag ===== */
        .badge {
            display: inline-block;
            padding: 4px 14px;
            border-radius: 50px;
            font-size: 0.8rem;
            font-weight: 600;
            background: var(--primary-bg);
            color: var(--primary);
            border: 1px solid rgba(26, 86, 219, 0.15);
            transition: all var(--transition);
        }
        .badge:hover {
            background: var(--primary);
            color: #fff;
        }
        .badge-secondary {
            background: #fef3c7;
            color: var(--secondary-dark);
            border-color: rgba(245, 158, 11, 0.20);
        }
        .badge-secondary:hover {
            background: var(--secondary);
            color: #fff;
        }
        .badge-accent {
            background: #d1fae5;
            color: #065f46;
            border-color: rgba(16, 185, 129, 0.20);
        }
        .badge-accent:hover {
            background: var(--accent);
            color: #fff;
        }

        /* ===== Header & Navigation ===== */
        .site-header {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: var(--header-h);
            background: rgba(255, 255, 255, 0.96);
            backdrop-filter: blur(16px);
            -webkit-backdrop-filter: blur(16px);
            border-bottom: 1px solid var(--border);
            z-index: 1000;
            transition: box-shadow var(--transition);
        }
        .site-header.scrolled {
            box-shadow: 0 4px 24px rgba(0, 0, 0, 0.06);
        }
        .header-inner {
            max-width: var(--max-width);
            margin: 0 auto;
            padding: 0 24px;
            height: var(--header-h);
            display: flex;
            align-items: center;
            justify-content: center;
            position: relative;
        }
        .nav-left,
        .nav-right {
            display: flex;
            align-items: center;
            gap: 8px;
            flex: 1;
        }
        .nav-right {
            justify-content: flex-end;
        }
        .nav-logo {
            font-size: 1.5rem;
            font-weight: 800;
            color: var(--text);
            letter-spacing: -0.5px;
            white-space: nowrap;
            margin: 0 20px;
            transition: opacity var(--transition);
        }
        .nav-logo:hover {
            opacity: 0.85;
            color: var(--text);
        }
        .nav-logo span {
            color: var(--primary);
        }
        .nav-link {
            padding: 8px 16px;
            border-radius: var(--radius-sm);
            font-weight: 500;
            font-size: 0.95rem;
            color: var(--text-light);
            transition: all var(--transition);
            position: relative;
        }
        .nav-link:hover {
            color: var(--primary);
            background: var(--primary-bg);
        }
        .nav-link.active {
            color: var(--primary);
            background: var(--primary-bg);
            font-weight: 600;
        }
        .nav-link.active::after {
            content: '';
            position: absolute;
            bottom: 2px;
            left: 50%;
            transform: translateX(-50%);
            width: 20px;
            height: 3px;
            background: var(--primary);
            border-radius: 4px;
        }
        .mobile-toggle {
            display: none;
            font-size: 1.4rem;
            color: var(--text);
            padding: 8px;
            border-radius: var(--radius-sm);
            transition: background var(--transition);
        }
        .mobile-toggle:hover {
            background: var(--bg-alt);
        }
        .mobile-menu {
            display: none;
            flex-direction: column;
            background: var(--bg);
            border-top: 1px solid var(--border);
            padding: 16px 24px 24px;
            gap: 6px;
            position: absolute;
            top: var(--header-h);
            left: 0;
            width: 100%;
            box-shadow: var(--shadow-lg);
            border-radius: 0 0 var(--radius) var(--radius);
        }
        .mobile-menu.open {
            display: flex;
        }
        .mobile-menu .nav-link {
            padding: 12px 16px;
            font-size: 1.05rem;
        }

        /* ===== Hero / Banner ===== */
        .category-hero {
            position: relative;
            min-height: 380px;
            display: flex;
            align-items: center;
            justify-content: center;
            text-align: center;
            padding: 80px 24px 60px;
            background: linear-gradient(135deg, rgba(15, 23, 42, 0.82), rgba(30, 64, 175, 0.78)), url('/assets/images/backpic/back-1.png') center center / cover no-repeat;
            color: #fff;
            overflow: hidden;
        }
        .category-hero::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 100%;
            height: 80px;
            background: linear-gradient(to top, var(--bg), transparent);
            pointer-events: none;
        }
        .category-hero .hero-content {
            max-width: 800px;
            position: relative;
            z-index: 2;
        }
        .category-hero h1 {
            color: #fff;
            font-size: 3rem;
            margin-bottom: 16px;
            letter-spacing: -0.02em;
        }
        .category-hero p {
            color: rgba(255, 255, 255, 0.85);
            font-size: 1.2rem;
            max-width: 620px;
            margin: 0 auto 28px;
        }
        .category-hero .hero-badges {
            display: flex;
            flex-wrap: wrap;
            justify-content: center;
            gap: 10px;
            margin-bottom: 24px;
        }
        .category-hero .hero-badges .badge {
            background: rgba(255, 255, 255, 0.15);
            color: #fff;
            border-color: rgba(255, 255, 255, 0.25);
            backdrop-filter: blur(4px);
        }
        .category-hero .hero-badges .badge:hover {
            background: rgba(255, 255, 255, 0.30);
            color: #fff;
        }

        /* ===== Tags Filter ===== */
        .tags-bar {
            display: flex;
            flex-wrap: wrap;
            justify-content: center;
            gap: 10px;
            padding: 32px 0 16px;
        }
        .tags-bar .tag-btn {
            padding: 8px 22px;
            border-radius: 50px;
            font-weight: 500;
            font-size: 0.9rem;
            background: var(--bg-alt);
            color: var(--text-light);
            border: 1px solid var(--border);
            transition: all var(--transition);
        }
        .tags-bar .tag-btn:hover {
            background: var(--primary-bg);
            color: var(--primary);
            border-color: var(--primary);
        }
        .tags-bar .tag-btn.active {
            background: var(--primary);
            color: #fff;
            border-color: var(--primary);
        }

        /* ===== Card Grid ===== */
        .card-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
            gap: 28px;
        }
        .card {
            background: var(--bg-card);
            border-radius: var(--radius);
            border: 1px solid var(--border);
            box-shadow: var(--shadow);
            overflow: hidden;
            transition: all var(--transition);
            display: flex;
            flex-direction: column;
        }
        .card:hover {
            transform: translateY(-6px);
            box-shadow: var(--shadow-hover);
            border-color: var(--primary-light);
        }
        .card-img {
            width: 100%;
            aspect-ratio: 16 / 10;
            object-fit: cover;
            display: block;
            background: var(--bg-alt);
        }
        .card-body {
            padding: 20px 22px 24px;
            flex: 1;
            display: flex;
            flex-direction: column;
        }
        .card-body .card-tags {
            display: flex;
            flex-wrap: wrap;
            gap: 6px;
            margin-bottom: 10px;
        }
        .card-body .card-tags .badge {
            font-size: 0.7rem;
            padding: 2px 10px;
        }
        .card-body h3 {
            font-size: 1.2rem;
            margin-bottom: 8px;
            line-height: 1.4;
        }
        .card-body h3 a {
            color: var(--text);
        }
        .card-body h3 a:hover {
            color: var(--primary);
        }
        .card-body p {
            font-size: 0.95rem;
            color: var(--text-muted);
            margin-bottom: 16px;
            flex: 1;
        }
        .card-body .card-meta {
            display: flex;
            align-items: center;
            justify-content: space-between;
            font-size: 0.85rem;
            color: var(--text-muted);
            border-top: 1px solid var(--border-light);
            padding-top: 14px;
            margin-top: auto;
        }
        .card-body .card-meta i {
            margin-right: 4px;
        }
        .card-body .card-link {
            font-weight: 600;
            color: var(--primary);
            font-size: 0.95rem;
            display: inline-flex;
            align-items: center;
            gap: 6px;
        }
        .card-body .card-link:hover {
            color: var(--primary-dark);
            gap: 10px;
        }

        /* ===== Stats / Data Row ===== */
        .stats-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
            gap: 28px;
            text-align: center;
        }
        .stat-item {
            background: var(--bg-card);
            border-radius: var(--radius);
            padding: 32px 20px;
            border: 1px solid var(--border);
            box-shadow: var(--shadow);
            transition: all var(--transition);
        }
        .stat-item:hover {
            transform: translateY(-4px);
            box-shadow: var(--shadow-hover);
        }
        .stat-item .stat-number {
            font-size: 2.6rem;
            font-weight: 800;
            color: var(--primary);
            line-height: 1.2;
            margin-bottom: 6px;
        }
        .stat-item .stat-label {
            font-size: 0.95rem;
            color: var(--text-muted);
            font-weight: 500;
        }
        .stat-item .stat-icon {
            font-size: 2rem;
            color: var(--primary-light);
            margin-bottom: 12px;
        }

        /* ===== Steps / Process ===== */
        .steps-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
            gap: 32px;
            counter-reset: step;
        }
        .step-card {
            background: var(--bg-card);
            border-radius: var(--radius);
            padding: 32px 24px;
            border: 1px solid var(--border);
            box-shadow: var(--shadow);
            text-align: center;
            position: relative;
            transition: all var(--transition);
        }
        .step-card:hover {
            transform: translateY(-4px);
            box-shadow: var(--shadow-hover);
        }
        .step-card .step-number {
            width: 48px;
            height: 48px;
            border-radius: 50%;
            background: var(--primary-bg);
            color: var(--primary);
            font-weight: 800;
            font-size: 1.3rem;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0 auto 16px;
            border: 2px solid rgba(26, 86, 219, 0.12);
        }
        .step-card h4 {
            font-size: 1.15rem;
            margin-bottom: 8px;
        }
        .step-card p {
            font-size: 0.9rem;
            color: var(--text-muted);
            margin-bottom: 0;
        }

        /* ===== FAQ ===== */
        .faq-list {
            max-width: 800px;
            margin: 0 auto;
            display: flex;
            flex-direction: column;
            gap: 12px;
        }
        .faq-item {
            background: var(--bg-card);
            border-radius: var(--radius-sm);
            border: 1px solid var(--border);
            overflow: hidden;
            transition: all var(--transition);
        }
        .faq-item:hover {
            border-color: var(--primary-light);
        }
        .faq-item summary {
            padding: 18px 24px;
            font-weight: 600;
            font-size: 1.05rem;
            cursor: pointer;
            display: flex;
            align-items: center;
            justify-content: space-between;
            list-style: none;
            transition: background var(--transition);
        }
        .faq-item summary::-webkit-details-marker {
            display: none;
        }
        .faq-item summary::after {
            content: '\f078';
            font-family: 'Font Awesome 6 Free';
            font-weight: 900;
            font-size: 0.85rem;
            color: var(--text-muted);
            transition: transform var(--transition);
        }
        .faq-item[open] summary::after {
            transform: rotate(180deg);
        }
        .faq-item summary:hover {
            background: var(--bg-alt);
        }
        .faq-item .faq-answer {
            padding: 0 24px 20px;
            color: var(--text-light);
            line-height: 1.8;
        }
        .faq-item .faq-answer p:last-child {
            margin-bottom: 0;
        }

        /* ===== CTA ===== */
        .cta-section {
            background: linear-gradient(135deg, var(--primary-dark), var(--primary));
            color: #fff;
            text-align: center;
            padding: 80px 24px;
            border-radius: var(--radius-lg);
            margin: 0 24px;
            position: relative;
            overflow: hidden;
        }
        .cta-section::before {
            content: '';
            position: absolute;
            inset: 0;
            background: url('/assets/images/backpic/back-2.png') center center / cover no-repeat;
            opacity: 0.08;
            pointer-events: none;
        }
        .cta-section .cta-content {
            position: relative;
            z-index: 2;
            max-width: 640px;
            margin: 0 auto;
        }
        .cta-section h2 {
            color: #fff;
            font-size: 2.2rem;
            margin-bottom: 12px;
        }
        .cta-section p {
            color: rgba(255, 255, 255, 0.85);
            font-size: 1.1rem;
            margin-bottom: 28px;
        }

        /* ===== Footer ===== */
        .site-footer {
            background: #0f172a;
            color: rgba(255, 255, 255, 0.75);
            padding: 60px 0 0;
            margin-top: 80px;
        }
        .site-footer .nav-logo {
            color: #fff;
            margin: 0 0 12px;
        }
        .site-footer .nav-logo span {
            color: var(--primary-light);
        }
        .site-footer a {
            color: rgba(255, 255, 255, 0.65);
        }
        .site-footer a:hover {
            color: #fff;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr 1.2fr;
            gap: 40px;
            padding-bottom: 40px;
            border-bottom: 1px solid rgba(255, 255, 255, 0.08);
        }
        .footer-brand p {
            font-size: 0.95rem;
            color: rgba(255, 255, 255, 0.55);
            margin-top: 12px;
            max-width: 320px;
        }
        .footer-col h4 {
            color: #fff;
            font-size: 1rem;
            margin-bottom: 16px;
            font-weight: 600;
        }
        .footer-col ul li {
            margin-bottom: 10px;
        }
        .footer-col ul li a {
            font-size: 0.9rem;
            display: inline-flex;
            align-items: center;
        }
        .footer-col ul li a:hover {
            padding-left: 4px;
        }
        .footer-bottom {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 24px 0;
            font-size: 0.85rem;
            color: rgba(255, 255, 255, 0.4);
            flex-wrap: wrap;
            gap: 16px;
        }
        .footer-bottom .social-links {
            display: flex;
            gap: 16px;
        }
        .footer-bottom .social-links a {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            width: 40px;
            height: 40px;
            border-radius: 50%;
            background: rgba(255, 255, 255, 0.06);
            color: rgba(255, 255, 255, 0.5);
            font-size: 1.1rem;
            transition: all var(--transition);
        }
        .footer-bottom .social-links a:hover {
            background: var(--primary);
            color: #fff;
            transform: translateY(-2px);
        }

        /* ===== Responsive ===== */
        @media (max-width: 1024px) {
            .footer-grid {
                grid-template-columns: 1fr 1fr;
                gap: 32px;
            }
            .category-hero h1 {
                font-size: 2.4rem;
            }
        }

        @media (max-width: 768px) {
            :root {
                --header-h: 64px;
            }
            .nav-left,
            .nav-right {
                display: none;
            }
            .mobile-toggle {
                display: block;
                position: absolute;
                right: 16px;
                top: 50%;
                transform: translateY(-50%);
            }
            .header-inner {
                justify-content: space-between;
            }
            .nav-logo {
                margin: 0;
                font-size: 1.3rem;
            }
            .category-hero {
                min-height: 300px;
                padding: 60px 20px 40px;
            }
            .category-hero h1 {
                font-size: 2rem;
            }
            .category-hero p {
                font-size: 1rem;
            }
            .section {
                padding: 48px 0;
            }
            .section-title {
                margin-bottom: 32px;
            }
            h2 {
                font-size: 1.7rem;
            }
            .card-grid {
                grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
                gap: 20px;
            }
            .stats-grid {
                grid-template-columns: repeat(2, 1fr);
                gap: 16px;
            }
            .stat-item .stat-number {
                font-size: 2rem;
            }
            .steps-grid {
                grid-template-columns: 1fr;
                gap: 20px;
            }
            .cta-section {
                margin: 0 16px;
                padding: 48px 20px;
                border-radius: var(--radius);
            }
            .cta-section h2 {
                font-size: 1.6rem;
            }
            .footer-grid {
                grid-template-columns: 1fr;
                gap: 28px;
            }
            .footer-bottom {
                flex-direction: column;
                text-align: center;
            }
            .tags-bar {
                gap: 8px;
            }
            .tags-bar .tag-btn {
                padding: 6px 16px;
                font-size: 0.8rem;
            }
        }

        @media (max-width: 520px) {
            .category-hero h1 {
                font-size: 1.6rem;
            }
            .category-hero p {
                font-size: 0.9rem;
            }
            .card-grid {
                grid-template-columns: 1fr;
            }
            .stats-grid {
                grid-template-columns: 1fr 1fr;
                gap: 12px;
            }
            .stat-item {
                padding: 20px 12px;
            }
            .stat-item .stat-number {
                font-size: 1.6rem;
            }
            .btn-lg {
                padding: 14px 24px;
                font-size: 1rem;
            }
            .container {
                padding: 0 16px;
            }
            .faq-item summary {
                padding: 14px 16px;
                font-size: 0.95rem;
            }
            .faq-item .faq-answer {
                padding: 0 16px 16px;
            }
        }

        /* ===== Utility ===== */
        .gap-8 {
            gap: 8px;
        }
        .mt-16 {
            margin-top: 16px;
        }
        .mt-24 {
            margin-top: 24px;
        }
        .mt-32 {
            margin-top: 32px;
        }
        .flex-center {
            display: flex;
            align-items: center;
            justify-content: center;
        }
        .flex-wrap {
            flex-wrap: wrap;
        }
        .sr-only {
            position: absolute;
            width: 1px;
            height: 1px;
            padding: 0;
            margin: -1px;
            overflow: hidden;
            clip: rect(0, 0, 0, 0);
            border: 0;
        }