/* roulang page: index */
/* ===== Design Tokens ===== */
        :root {
            --primary: #1a2a6c;
            --primary-light: #2a4a8f;
            --primary-dark: #0f1a4a;
            --accent: #f6ad55;
            --accent-light: #fbd38d;
            --accent-dark: #dd6b20;
            --bg: #f7fafc;
            --bg-alt: #edf2f7;
            --bg-dark: #1a202c;
            --text: #1e293b;
            --text-light: #64748b;
            --text-inverse: #ffffff;
            --border: #e2e8f0;
            --radius: 16px;
            --radius-sm: 10px;
            --radius-xs: 6px;
            --shadow: 0 4px 24px rgba(0,0,0,0.06);
            --shadow-lg: 0 12px 40px rgba(0,0,0,0.10);
            --shadow-xl: 0 20px 60px rgba(0,0,0,0.14);
            --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
            --font: 'Segoe UI', system-ui, -apple-system, sans-serif;
            --container: 1200px;
            --nav-height: 72px;
        }

        /* ===== Reset & Base ===== */
        *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
        html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }
        body {
            font-family: var(--font);
            font-size: 16px;
            line-height: 1.6;
            color: var(--text);
            background: var(--bg);
        }
        a { color: var(--primary); text-decoration: none; transition: color var(--transition); }
        a:hover { color: var(--accent-dark); }
        img { max-width: 100%; height: auto; display: block; border-radius: var(--radius-sm); }
        button, input, textarea { font-family: inherit; font-size: 1rem; }
        ul, ol { list-style: none; }
        h1, h2, h3, h4, h5, h6 { line-height: 1.3; font-weight: 700; color: var(--primary-dark); }
        .container { max-width: var(--container); margin: 0 auto; padding: 0 24px; }
        .section { padding: 80px 0; }
        .section-title { font-size: 2.2rem; text-align: center; margin-bottom: 16px; letter-spacing: -0.02em; }
        .section-subtitle { font-size: 1.1rem; color: var(--text-light); text-align: center; max-width: 640px; margin: 0 auto 48px; line-height: 1.7; }
        .text-center { text-align: center; }
        .text-accent { color: var(--accent-dark); }

        /* ===== Buttons ===== */
        .btn {
            display: inline-flex; align-items: center; gap: 10px;
            padding: 14px 32px; border-radius: 50px; font-weight: 600; font-size: 1rem;
            border: none; cursor: pointer; transition: all var(--transition);
            text-decoration: none; letter-spacing: 0.01em;
        }
        .btn-primary { background: var(--primary); color: #fff; box-shadow: 0 4px 14px rgba(26,42,108,0.30); }
        .btn-primary:hover { background: var(--primary-light); transform: translateY(-2px); box-shadow: 0 8px 28px rgba(26,42,108,0.35); color: #fff; }
        .btn-accent { background: var(--accent); color: var(--primary-dark); box-shadow: 0 4px 14px rgba(246,173,85,0.35); }
        .btn-accent:hover { background: var(--accent-light); transform: translateY(-2px); box-shadow: 0 8px 28px rgba(246,173,85,0.40); color: var(--primary-dark); }
        .btn-outline { background: transparent; color: var(--primary); border: 2px solid var(--primary); }
        .btn-outline:hover { background: var(--primary); color: #fff; transform: translateY(-2px); }
        .btn-sm { padding: 10px 20px; font-size: 0.9rem; }
        .btn-lg { padding: 18px 42px; font-size: 1.15rem; }

        /* ===== Header / Nav ===== */
        .site-header {
            position: sticky; top: 0; z-index: 1000;
            background: rgba(255,255,255,0.92);
            backdrop-filter: blur(16px);
            border-bottom: 1px solid var(--border);
            height: var(--nav-height);
            box-shadow: 0 1px 8px rgba(0,0,0,0.04);
        }
        .header-inner {
            display: flex; align-items: center; justify-content: space-between;
            height: 100%; max-width: var(--container); margin: 0 auto; padding: 0 24px;
            gap: 20px;
        }
        .logo {
            font-size: 1.5rem; font-weight: 800; color: var(--primary);
            letter-spacing: -0.03em; white-space: nowrap;
            display: flex; align-items: center; gap: 8px;
        }
        .logo i { color: var(--accent); font-size: 1.6rem; }
        .logo:hover { color: var(--primary); }

        /* Search Bar */
        .search-wrap {
            flex: 1; max-width: 480px; position: relative;
        }
        .search-wrap input {
            width: 100%; padding: 10px 20px 10px 44px;
            border: 2px solid var(--border); border-radius: 50px;
            background: var(--bg); font-size: 0.95rem;
            transition: all var(--transition); outline: none;
        }
        .search-wrap input:focus { border-color: var(--primary); background: #fff; box-shadow: 0 0 0 4px rgba(26,42,108,0.08); }
        .search-wrap i {
            position: absolute; left: 16px; top: 50%; transform: translateY(-50%);
            color: var(--text-light); font-size: 1rem;
        }

        /* Nav Links */
        .nav-links { display: flex; align-items: center; gap: 8px; }
        .nav-links a {
            padding: 8px 18px; border-radius: 50px; font-weight: 500; font-size: 0.95rem;
            color: var(--text); transition: all var(--transition); white-space: nowrap;
        }
        .nav-links a:hover { background: var(--bg-alt); color: var(--primary); }
        .nav-links a.active { background: var(--primary); color: #fff; box-shadow: 0 2px 12px rgba(26,42,108,0.20); }
        .nav-links a.active:hover { background: var(--primary-light); color: #fff; }

        /* Mobile Toggle */
        .mobile-toggle { display: none; background: none; border: none; font-size: 1.6rem; color: var(--primary); cursor: pointer; padding: 4px; }

        /* ===== Hero ===== */
        .hero {
            position: relative; min-height: 520px; display: flex; align-items: center;
            background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 50%, var(--primary-light) 100%);
            overflow: hidden; isolation: isolate;
        }
        .hero-bg {
            position: absolute; inset: 0; z-index: 0;
            background-image: url('/assets/images/backpic/back-1.png');
            background-size: cover; background-position: center; background-blend-mode: overlay;
            opacity: 0.18;
        }
        .hero-overlay {
            position: absolute; inset: 0; z-index: 1;
            background: radial-gradient(ellipse at 30% 50%, rgba(26,42,108,0.30) 0%, transparent 70%);
        }
        .hero-content { position: relative; z-index: 2; padding: 60px 0; max-width: 720px; }
        .hero h1 { font-size: 3.2rem; color: #fff; margin-bottom: 20px; letter-spacing: -0.02em; line-height: 1.2; }
        .hero p { font-size: 1.2rem; color: rgba(255,255,255,0.80); margin-bottom: 32px; line-height: 1.7; max-width: 560px; }
        .hero .btn-group { display: flex; gap: 16px; flex-wrap: wrap; }
        .hero .btn-accent { background: var(--accent); color: var(--primary-dark); }
        .hero .btn-outline { border-color: rgba(255,255,255,0.50); color: #fff; }
        .hero .btn-outline:hover { background: rgba(255,255,255,0.12); border-color: #fff; color: #fff; }

        /* ===== Feature Cards ===== */
        .features-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; }
        .feature-card {
            background: #fff; border-radius: var(--radius); padding: 36px 28px;
            box-shadow: var(--shadow); transition: all var(--transition);
            border: 1px solid var(--border); text-align: center;
        }
        .feature-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
        .feature-card .icon {
            width: 64px; height: 64px; border-radius: 50%;
            background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
            color: #fff; display: flex; align-items: center; justify-content: center;
            font-size: 1.6rem; margin: 0 auto 20px; box-shadow: 0 4px 12px rgba(26,42,108,0.20);
        }
        .feature-card h3 { font-size: 1.25rem; margin-bottom: 12px; }
        .feature-card p { color: var(--text-light); font-size: 0.95rem; line-height: 1.7; }

        /* ===== Category Entry ===== */
        .category-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 28px; }
        .category-card {
            position: relative; border-radius: var(--radius); overflow: hidden;
            background: #fff; box-shadow: var(--shadow); transition: all var(--transition);
            border: 1px solid var(--border); display: flex; flex-direction: column;
        }
        .category-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
        .category-card img { width: 100%; height: 200px; object-fit: cover; }
        .category-card .body { padding: 24px 28px; flex: 1; }
        .category-card .body h3 { font-size: 1.2rem; margin-bottom: 8px; }
        .category-card .body p { color: var(--text-light); font-size: 0.95rem; line-height: 1.7; margin-bottom: 16px; }
        .category-card .badge {
            display: inline-block; padding: 4px 14px; border-radius: 50px;
            background: var(--bg-alt); color: var(--primary); font-size: 0.8rem; font-weight: 600;
        }

        /* ===== News / List ===== */
        .news-list { display: grid; grid-template-columns: 1fr; gap: 16px; }
        .news-item {
            display: flex; align-items: center; gap: 20px;
            background: #fff; padding: 20px 24px; border-radius: var(--radius-sm);
            box-shadow: var(--shadow); border: 1px solid var(--border);
            transition: all var(--transition);
        }
        .news-item:hover { transform: translateX(4px); box-shadow: var(--shadow-lg); }
        .news-item .num {
            width: 40px; height: 40px; border-radius: 50%;
            background: var(--bg-alt); color: var(--primary);
            display: flex; align-items: center; justify-content: center;
            font-weight: 700; font-size: 0.9rem; flex-shrink: 0;
        }
        .news-item .info { flex: 1; }
        .news-item .info h4 { font-size: 1.05rem; font-weight: 600; margin-bottom: 4px; }
        .news-item .info h4 a { color: var(--text); }
        .news-item .info h4 a:hover { color: var(--primary); }
        .news-item .info .meta { font-size: 0.85rem; color: var(--text-light); display: flex; gap: 16px; }
        .news-item .info .meta span { display: flex; align-items: center; gap: 4px; }
        .news-item .tag {
            padding: 4px 12px; border-radius: 50px; background: var(--accent-light);
            color: var(--primary-dark); font-size: 0.75rem; font-weight: 600; flex-shrink: 0;
        }
        .empty-news { text-align: center; padding: 40px; color: var(--text-light); font-size: 1.05rem; background: #fff; border-radius: var(--radius-sm); border: 1px dashed var(--border); }

        /* ===== Stats / Process ===== */
        .stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
        .stat-card {
            text-align: center; background: #fff; border-radius: var(--radius);
            padding: 32px 20px; box-shadow: var(--shadow); border: 1px solid var(--border);
            transition: all var(--transition);
        }
        .stat-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
        .stat-card .number { font-size: 2.6rem; font-weight: 800; color: var(--primary); line-height: 1.2; }
        .stat-card .label { font-size: 0.95rem; color: var(--text-light); margin-top: 8px; }

        /* ===== FAQ ===== */
        .faq-list { max-width: 800px; margin: 0 auto; display: flex; flex-direction: column; gap: 12px; }
        .faq-item {
            background: #fff; border-radius: var(--radius-sm); border: 1px solid var(--border);
            overflow: hidden; transition: all var(--transition); box-shadow: var(--shadow);
        }
        .faq-item summary {
            padding: 20px 24px; font-weight: 600; font-size: 1.05rem;
            cursor: pointer; display: flex; align-items: center; gap: 12px;
            list-style: none; transition: background var(--transition);
        }
        .faq-item summary::-webkit-details-marker { display: none; }
        .faq-item summary i { color: var(--accent); font-size: 1.1rem; transition: transform var(--transition); }
        .faq-item[open] summary i { transform: rotate(180deg); }
        .faq-item[open] summary { background: var(--bg-alt); }
        .faq-item .answer { padding: 0 24px 20px; color: var(--text-light); line-height: 1.8; }

        /* ===== CTA ===== */
        .cta-section {
            background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 100%);
            padding: 80px 0; text-align: center; position: relative; overflow: hidden;
        }
        .cta-section::before {
            content: ''; position: absolute; inset: 0;
            background-image: url('/assets/images/backpic/back-2.png');
            background-size: cover; background-position: center; opacity: 0.08;
        }
        .cta-section .container { position: relative; z-index: 1; }
        .cta-section h2 { font-size: 2.4rem; color: #fff; margin-bottom: 16px; }
        .cta-section p { font-size: 1.1rem; color: rgba(255,255,255,0.75); max-width: 560px; margin: 0 auto 32px; }
        .cta-section .btn { background: var(--accent); color: var(--primary-dark); }
        .cta-section .btn:hover { background: var(--accent-light); transform: translateY(-2px); }

        /* ===== Footer ===== */
        .site-footer {
            background: var(--bg-dark); color: rgba(255,255,255,0.70);
            padding: 60px 0 30px; font-size: 0.95rem;
        }
        .footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 40px; }
        .footer-brand .logo { color: #fff; margin-bottom: 16px; }
        .footer-brand .logo i { color: var(--accent); }
        .footer-brand p { line-height: 1.8; max-width: 320px; }
        .footer-col h4 { color: #fff; font-size: 1.05rem; margin-bottom: 16px; font-weight: 600; }
        .footer-col a { display: block; color: rgba(255,255,255,0.60); padding: 4px 0; transition: all var(--transition); }
        .footer-col a:hover { color: var(--accent); padding-left: 4px; }
        .footer-bottom {
            border-top: 1px solid rgba(255,255,255,0.08); padding-top: 24px;
            display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 12px;
            font-size: 0.85rem; color: rgba(255,255,255,0.40);
        }

        /* ===== Article Page ===== */
        .article-header {
            background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 100%);
            padding: 60px 0; position: relative; overflow: hidden;
        }
        .article-header::before {
            content: ''; position: absolute; inset: 0;
            background-image: url('/assets/images/backpic/back-3.png');
            background-size: cover; background-position: center; opacity: 0.10;
        }
        .article-header .container { position: relative; z-index: 1; }
        .article-header h1 { font-size: 2.4rem; color: #fff; margin-bottom: 16px; max-width: 800px; }
        .article-header .meta { display: flex; gap: 24px; color: rgba(255,255,255,0.65); font-size: 0.95rem; flex-wrap: wrap; }
        .article-header .meta span { display: flex; align-items: center; gap: 6px; }
        .article-body { max-width: 800px; margin: 0 auto; padding: 48px 0; }
        .article-body .content { font-size: 1.05rem; line-height: 1.9; color: var(--text); }
        .article-body .content p { margin-bottom: 20px; }
        .article-body .content img { margin: 24px 0; border-radius: var(--radius-sm); }
        .article-body .content h2, .article-body .content h3 { margin-top: 36px; margin-bottom: 16px; }
        .article-not-found { text-align: center; padding: 80px 0; }
        .article-not-found i { font-size: 3rem; color: var(--text-light); margin-bottom: 20px; }
        .article-not-found h2 { font-size: 1.8rem; margin-bottom: 12px; }
        .article-not-found p { color: var(--text-light); margin-bottom: 24px; }

        /* ===== Category Page ===== */
        .category-banner {
            background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
            padding: 60px 0; position: relative; overflow: hidden;
        }
        .category-banner::before {
            content: ''; position: absolute; inset: 0;
            background-image: url('/assets/images/backpic/back-1.png');
            background-size: cover; background-position: center; opacity: 0.10;
        }
        .category-banner .container { position: relative; z-index: 1; }
        .category-banner h1 { font-size: 2.4rem; color: #fff; margin-bottom: 16px; }
        .category-banner p { font-size: 1.1rem; color: rgba(255,255,255,0.75); max-width: 560px; }
        .category-grid-page { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; }

        /* ===== Breadcrumb ===== */
        .breadcrumb { display: flex; gap: 8px; align-items: center; font-size: 0.9rem; color: var(--text-light); margin-bottom: 24px; flex-wrap: wrap; }
        .breadcrumb a { color: var(--primary); }
        .breadcrumb a:hover { color: var(--accent-dark); }
        .breadcrumb span { color: var(--text-light); }
        .breadcrumb i { font-size: 0.7rem; color: var(--text-light); }

        /* ===== Responsive ===== */
        @media (max-width: 1024px) {
            .features-grid { grid-template-columns: repeat(2, 1fr); }
            .category-grid-page { grid-template-columns: repeat(2, 1fr); }
            .footer-grid { grid-template-columns: 1fr 1fr; }
            .stats-grid { grid-template-columns: repeat(2, 1fr); }
        }

        @media (max-width: 768px) {
            .header-inner { gap: 12px; }
            .nav-links { display: none; }
            .mobile-toggle { display: block; }
            .nav-links.open {
                display: flex; flex-direction: column; position: absolute;
                top: var(--nav-height); left: 0; right: 0; background: #fff;
                padding: 20px 24px; border-bottom: 1px solid var(--border);
                box-shadow: var(--shadow-lg); gap: 4px; z-index: 999;
            }
            .nav-links.open a { padding: 12px 20px; border-radius: var(--radius-xs); }
            .search-wrap { max-width: 200px; }
            .hero h1 { font-size: 2.2rem; }
            .hero p { font-size: 1rem; }
            .section-title { font-size: 1.7rem; }
            .features-grid { grid-template-columns: 1fr; }
            .category-grid { grid-template-columns: 1fr; }
            .category-grid-page { grid-template-columns: 1fr; }
            .stats-grid { grid-template-columns: repeat(2, 1fr); }
            .footer-grid { grid-template-columns: 1fr; }
            .article-header h1 { font-size: 1.7rem; }
            .hero { min-height: 380px; }
            .section { padding: 48px 0; }
            .cta-section { padding: 48px 0; }
            .cta-section h2 { font-size: 1.6rem; }
        }

        @media (max-width: 520px) {
            .header-inner { padding: 0 16px; gap: 8px; }
            .search-wrap { max-width: 140px; }
            .search-wrap input { padding: 8px 12px 8px 36px; font-size: 0.85rem; }
            .search-wrap i { left: 12px; font-size: 0.85rem; }
            .logo { font-size: 1.15rem; }
            .logo i { font-size: 1.2rem; }
            .hero h1 { font-size: 1.7rem; }
            .hero p { font-size: 0.95rem; }
            .hero .btn-group { flex-direction: column; gap: 12px; }
            .hero .btn { width: 100%; justify-content: center; }
            .section-title { font-size: 1.4rem; }
            .news-item { flex-direction: column; align-items: flex-start; gap: 12px; }
            .news-item .tag { align-self: flex-start; }
            .stat-card .number { font-size: 2rem; }
            .footer-bottom { flex-direction: column; text-align: center; }
            .category-banner h1 { font-size: 1.6rem; }
            .article-header h1 { font-size: 1.4rem; }
        }

        /* ===== Utility ===== */
        .mt-8 { margin-top: 8px; }
        .mt-16 { margin-top: 16px; }
        .mt-24 { margin-top: 24px; }
        .mb-16 { margin-bottom: 16px; }
        .gap-12 { gap: 12px; }
        .flex-center { display: flex; align-items: center; justify-content: center; }
        .tag {
            display: inline-block; padding: 4px 14px; border-radius: 50px;
            background: var(--bg-alt); color: var(--primary); font-size: 0.8rem; font-weight: 600;
        }
        .tag-accent { background: var(--accent-light); color: var(--primary-dark); }
        .divider { height: 1px; background: var(--border); margin: 16px 0; }
        .back-home { display: inline-flex; align-items: center; gap: 8px; color: var(--primary); font-weight: 500; }
        .back-home:hover { gap: 12px; }

/* roulang page: category1 */
/* ===== Design Variables ===== */
        :root {
            --primary: #4f46e5;
            --primary-light: #818cf8;
            --primary-dark: #3730a3;
            --secondary: #f59e0b;
            --secondary-light: #fbbf24;
            --accent: #10b981;
            --bg: #ffffff;
            --bg-alt: #f8fafc;
            --bg-card: #ffffff;
            --bg-dark: #0f172a;
            --text: #1e293b;
            --text-light: #64748b;
            --text-white: #f1f5f9;
            --border: #e2e8f0;
            --border-light: #f1f5f9;
            --radius: 12px;
            --radius-sm: 6px;
            --radius-lg: 20px;
            --shadow: 0 4px 24px rgba(0, 0, 0, 0.06);
            --shadow-lg: 0 12px 48px rgba(0, 0, 0, 0.10);
            --shadow-hover: 0 20px 56px rgba(79, 70, 229, 0.15);
            --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
            --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
            --container: 1200px;
            --nav-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);
            font-size: 16px;
            line-height: 1.7;
            color: var(--text);
            background: var(--bg);
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
            overflow-x: hidden;
        }
        a {
            color: var(--primary);
            text-decoration: none;
            transition: color var(--transition);
        }
        a:hover {
            color: var(--primary-dark);
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
            border-radius: var(--radius-sm);
        }
        button,
        input,
        textarea,
        select {
            font-family: inherit;
            font-size: inherit;
            line-height: inherit;
            border: none;
            outline: none;
            background: none;
        }
        button {
            cursor: pointer;
        }
        ul,
        ol {
            list-style: none;
        }
        h1,
        h2,
        h3,
        h4,
        h5,
        h6 {
            line-height: 1.3;
            font-weight: 700;
            color: var(--text);
        }
        h1 {
            font-size: clamp(2.2rem, 6vw, 3.6rem);
        }
        h2 {
            font-size: clamp(1.6rem, 4vw, 2.4rem);
        }
        h3 {
            font-size: clamp(1.2rem, 2.5vw, 1.6rem);
        }
        h4 {
            font-size: 1.1rem;
        }
        p {
            margin-bottom: 1rem;
            color: var(--text-light);
        }
        .container {
            max-width: var(--container);
            margin: 0 auto;
            padding: 0 24px;
        }

        /* ===== Header & Nav ===== */
        .site-header {
            position: sticky;
            top: 0;
            z-index: 1000;
            background: rgba(255, 255, 255, 0.92);
            backdrop-filter: blur(16px);
            -webkit-backdrop-filter: blur(16px);
            border-bottom: 1px solid var(--border);
            height: var(--nav-height);
            display: flex;
            align-items: center;
            transition: box-shadow var(--transition);
        }
        .site-header.scrolled {
            box-shadow: 0 4px 24px rgba(0, 0, 0, 0.06);
        }
        .header-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            width: 100%;
            gap: 16px;
        }
        .logo {
            display: flex;
            align-items: center;
            gap: 10px;
            font-size: 1.35rem;
            font-weight: 800;
            color: var(--primary);
            white-space: nowrap;
            flex-shrink: 0;
        }
        .logo i {
            font-size: 1.5rem;
            color: var(--secondary);
        }
        .logo span {
            background: linear-gradient(135deg, var(--primary), var(--primary-light));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        .nav-links {
            display: flex;
            align-items: center;
            gap: 8px;
            flex-shrink: 0;
        }
        .nav-links a {
            padding: 8px 18px;
            border-radius: 40px;
            font-weight: 500;
            font-size: 0.95rem;
            color: var(--text-light);
            transition: all var(--transition);
            position: relative;
        }
        .nav-links a:hover {
            color: var(--primary);
            background: rgba(79, 70, 229, 0.06);
        }
        .nav-links a.active {
            color: #fff;
            background: var(--primary);
            box-shadow: 0 4px 16px rgba(79, 70, 229, 0.30);
        }
        .nav-links a.active:hover {
            background: var(--primary-dark);
            color: #fff;
        }
        .nav-search {
            flex: 1;
            max-width: 420px;
            position: relative;
            margin: 0 12px;
        }
        .nav-search input {
            width: 100%;
            padding: 10px 20px 10px 44px;
            border-radius: 40px;
            background: var(--bg-alt);
            border: 1.5px solid var(--border);
            font-size: 0.9rem;
            color: var(--text);
            transition: all var(--transition);
        }
        .nav-search input:focus {
            border-color: var(--primary-light);
            background: #fff;
            box-shadow: 0 0 0 4px rgba(79, 70, 229, 0.10);
        }
        .nav-search input::placeholder {
            color: var(--text-light);
        }
        .nav-search .search-icon {
            position: absolute;
            left: 16px;
            top: 50%;
            transform: translateY(-50%);
            color: var(--text-light);
            font-size: 0.95rem;
            pointer-events: none;
        }
        .nav-actions {
            display: flex;
            align-items: center;
            gap: 10px;
            flex-shrink: 0;
        }
        .nav-actions .btn-ghost {
            padding: 8px 18px;
            border-radius: 40px;
            font-weight: 500;
            font-size: 0.9rem;
            color: var(--text-light);
            transition: all var(--transition);
        }
        .nav-actions .btn-ghost:hover {
            color: var(--primary);
            background: rgba(79, 70, 229, 0.06);
        }
        .nav-actions .btn-primary {
            padding: 9px 22px;
            border-radius: 40px;
            font-weight: 600;
            font-size: 0.9rem;
            color: #fff;
            background: var(--primary);
            transition: all var(--transition);
            box-shadow: 0 4px 14px rgba(79, 70, 229, 0.25);
        }
        .nav-actions .btn-primary:hover {
            background: var(--primary-dark);
            box-shadow: 0 6px 24px rgba(79, 70, 229, 0.35);
            transform: translateY(-1px);
        }
        .mobile-toggle {
            display: none;
            font-size: 1.5rem;
            color: var(--text);
            padding: 6px 10px;
            border-radius: var(--radius-sm);
            cursor: pointer;
            transition: background var(--transition);
            background: none;
            border: none;
        }
        .mobile-toggle:hover {
            background: var(--bg-alt);
        }

        /* ===== Hero / Banner ===== */
        .page-hero {
            position: relative;
            padding: 100px 0 80px;
            background: linear-gradient(135deg, #0f172a 0%, #1e293b 50%, #0f172a 100%);
            overflow: hidden;
            min-height: 340px;
            display: flex;
            align-items: center;
        }
        .page-hero::before {
            content: '';
            position: absolute;
            inset: 0;
            background: url('/assets/images/backpic/back-1.png') center center / cover no-repeat;
            opacity: 0.18;
            mix-blend-mode: overlay;
        }
        .page-hero::after {
            content: '';
            position: absolute;
            inset: 0;
            background: radial-gradient(ellipse at 30% 50%, rgba(79, 70, 229, 0.20) 0%, transparent 70%);
            pointer-events: none;
        }
        .page-hero .container {
            position: relative;
            z-index: 2;
            text-align: center;
        }
        .page-hero .breadcrumb {
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            font-size: 0.85rem;
            color: rgba(255, 255, 255, 0.6);
            margin-bottom: 20px;
        }
        .page-hero .breadcrumb a {
            color: rgba(255, 255, 255, 0.7);
            transition: color var(--transition);
        }
        .page-hero .breadcrumb a:hover {
            color: #fff;
        }
        .page-hero .breadcrumb i {
            font-size: 0.7rem;
            color: rgba(255, 255, 255, 0.3);
        }
        .page-hero h1 {
            color: #fff;
            font-weight: 800;
            letter-spacing: -0.02em;
            margin-bottom: 16px;
            text-shadow: 0 4px 32px rgba(0, 0, 0, 0.3);
        }
        .page-hero h1 i {
            color: var(--secondary);
            margin-right: 12px;
        }
        .page-hero p {
            color: rgba(255, 255, 255, 0.75);
            font-size: 1.15rem;
            max-width: 640px;
            margin: 0 auto 0;
            line-height: 1.7;
        }
        .hero-tags {
            display: flex;
            flex-wrap: wrap;
            gap: 10px;
            justify-content: center;
            margin-top: 28px;
        }
        .hero-tags .tag {
            padding: 6px 18px;
            border-radius: 40px;
            font-size: 0.8rem;
            font-weight: 500;
            background: rgba(255, 255, 255, 0.10);
            color: rgba(255, 255, 255, 0.8);
            border: 1px solid rgba(255, 255, 255, 0.12);
            backdrop-filter: blur(4px);
        }

        /* ===== Sections ===== */
        .section {
            padding: 80px 0;
        }
        .section-alt {
            background: var(--bg-alt);
        }
        .section-dark {
            background: var(--bg-dark);
            color: var(--text-white);
        }
        .section-dark h2,
        .section-dark h3 {
            color: #fff;
        }
        .section-dark p {
            color: rgba(255, 255, 255, 0.7);
        }
        .section-header {
            text-align: center;
            margin-bottom: 52px;
        }
        .section-header h2 {
            margin-bottom: 12px;
            position: relative;
            display: inline-block;
        }
        .section-header h2::after {
            content: '';
            display: block;
            width: 60px;
            height: 4px;
            border-radius: 4px;
            background: linear-gradient(90deg, var(--primary), var(--secondary));
            margin: 14px auto 0;
        }
        .section-header p {
            max-width: 560px;
            margin: 0 auto;
            font-size: 1.05rem;
        }

        /* ===== Cards ===== */
        .card-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
            gap: 28px;
        }
        .card {
            background: var(--bg-card);
            border-radius: var(--radius);
            box-shadow: var(--shadow);
            border: 1px solid var(--border-light);
            padding: 28px 24px;
            transition: all var(--transition);
            overflow: hidden;
        }
        .card:hover {
            transform: translateY(-6px);
            box-shadow: var(--shadow-hover);
            border-color: var(--primary-light);
        }
        .card .card-icon {
            width: 52px;
            height: 52px;
            border-radius: 14px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.4rem;
            color: #fff;
            margin-bottom: 18px;
            background: linear-gradient(135deg, var(--primary), var(--primary-light));
        }
        .card .card-icon.alt {
            background: linear-gradient(135deg, var(--secondary), var(--secondary-light));
            color: #1e293b;
        }
        .card .card-icon.green {
            background: linear-gradient(135deg, var(--accent), #34d399);
        }
        .card h3 {
            margin-bottom: 10px;
            font-size: 1.2rem;
        }
        .card p {
            font-size: 0.95rem;
            margin-bottom: 0;
        }
        .card .card-img {
            border-radius: var(--radius-sm);
            margin-bottom: 18px;
            width: 100%;
            height: 180px;
            object-fit: cover;
            background: var(--bg-alt);
        }
        .card .card-tag {
            display: inline-block;
            padding: 2px 14px;
            border-radius: 40px;
            font-size: 0.75rem;
            font-weight: 600;
            background: rgba(79, 70, 229, 0.08);
            color: var(--primary);
            margin-bottom: 12px;
        }

        /* ===== Steps ===== */
        .steps-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 32px;
            counter-reset: step;
        }
        .step-item {
            text-align: center;
            padding: 28px 16px;
            position: relative;
        }
        .step-item::before {
            counter-increment: step;
            content: counter(step);
            display: flex;
            align-items: center;
            justify-content: center;
            width: 48px;
            height: 48px;
            border-radius: 50%;
            background: var(--primary);
            color: #fff;
            font-weight: 700;
            font-size: 1.2rem;
            margin: 0 auto 18px;
            box-shadow: 0 8px 24px rgba(79, 70, 229, 0.25);
        }
        .step-item h4 {
            margin-bottom: 8px;
        }
        .step-item p {
            font-size: 0.9rem;
            margin-bottom: 0;
        }
        .step-item .step-line {
            display: none;
        }

        /* ===== Stats ===== */
        .stats-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
            gap: 28px;
            text-align: center;
        }
        .stat-item .stat-number {
            font-size: clamp(2.2rem, 5vw, 3.2rem);
            font-weight: 800;
            background: linear-gradient(135deg, var(--primary), var(--secondary));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            line-height: 1.2;
        }
        .stat-item .stat-label {
            font-size: 0.95rem;
            color: var(--text-light);
            margin-top: 6px;
        }
        .section-dark .stat-item .stat-label {
            color: rgba(255, 255, 255, 0.65);
        }

        /* ===== Features List ===== */
        .features-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
            gap: 24px;
        }
        .feature-item {
            display: flex;
            gap: 16px;
            padding: 20px;
            border-radius: var(--radius);
            background: var(--bg-card);
            border: 1px solid var(--border-light);
            transition: all var(--transition);
        }
        .feature-item:hover {
            border-color: var(--primary-light);
            box-shadow: var(--shadow);
        }
        .feature-item .fi-icon {
            flex-shrink: 0;
            width: 44px;
            height: 44px;
            border-radius: 12px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.1rem;
            color: #fff;
            background: var(--primary);
        }
        .feature-item .fi-icon.alt {
            background: var(--secondary);
            color: #1e293b;
        }
        .feature-item .fi-icon.green {
            background: var(--accent);
        }
        .feature-item h4 {
            font-size: 1rem;
            margin-bottom: 4px;
        }
        .feature-item p {
            font-size: 0.88rem;
            margin-bottom: 0;
        }

        /* ===== FAQ ===== */
        .faq-list {
            max-width: 780px;
            margin: 0 auto;
            display: flex;
            flex-direction: column;
            gap: 12px;
        }
        .faq-item {
            background: var(--bg-card);
            border-radius: var(--radius);
            border: 1px solid var(--border);
            overflow: hidden;
            transition: all var(--transition);
        }
        .faq-item:hover {
            border-color: var(--primary-light);
        }
        .faq-item .faq-q {
            padding: 18px 24px;
            font-weight: 600;
            font-size: 1rem;
            color: var(--text);
            cursor: pointer;
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 12px;
            user-select: none;
            transition: background var(--transition);
        }
        .faq-item .faq-q:hover {
            background: rgba(79, 70, 229, 0.03);
        }
        .faq-item .faq-q i {
            font-size: 0.85rem;
            color: var(--text-light);
            transition: transform var(--transition);
            flex-shrink: 0;
        }
        .faq-item.open .faq-q i {
            transform: rotate(180deg);
            color: var(--primary);
        }
        .faq-item .faq-a {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.4s ease, padding 0.3s ease;
            padding: 0 24px;
            color: var(--text-light);
            font-size: 0.95rem;
            line-height: 1.7;
        }
        .faq-item.open .faq-a {
            max-height: 300px;
            padding: 0 24px 20px;
        }

        /* ===== CTA ===== */
        .cta-section {
            padding: 80px 0;
            background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
            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;
            mix-blend-mode: overlay;
        }
        .cta-section .container {
            position: relative;
            z-index: 2;
            text-align: center;
        }
        .cta-section h2 {
            color: #fff;
            margin-bottom: 16px;
        }
        .cta-section p {
            color: rgba(255, 255, 255, 0.8);
            max-width: 560px;
            margin: 0 auto 32px;
            font-size: 1.05rem;
        }
        .cta-section .btn-cta {
            display: inline-flex;
            align-items: center;
            gap: 10px;
            padding: 16px 40px;
            border-radius: 60px;
            font-weight: 700;
            font-size: 1rem;
            color: var(--primary);
            background: #fff;
            transition: all var(--transition);
            box-shadow: 0 8px 32px rgba(0, 0, 0, 0.15);
        }
        .cta-section .btn-cta:hover {
            transform: translateY(-3px);
            box-shadow: 0 16px 48px rgba(0, 0, 0, 0.25);
            color: var(--primary-dark);
        }
        .cta-section .btn-cta i {
            font-size: 1.1rem;
        }

        /* ===== Footer ===== */
        .site-footer {
            background: var(--bg-dark);
            color: var(--text-white);
            padding: 60px 0 30px;
        }
        .site-footer .footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr 1fr;
            gap: 40px;
            margin-bottom: 40px;
        }
        .site-footer .footer-brand .logo {
            font-size: 1.3rem;
            color: #fff;
            margin-bottom: 16px;
        }
        .site-footer .footer-brand .logo i {
            color: var(--secondary);
        }
        .site-footer .footer-brand p {
            color: rgba(255, 255, 255, 0.6);
            font-size: 0.9rem;
            max-width: 320px;
            line-height: 1.7;
        }
        .site-footer .footer-col h4 {
            color: #fff;
            font-size: 0.95rem;
            margin-bottom: 18px;
            font-weight: 600;
        }
        .site-footer .footer-col a {
            display: block;
            color: rgba(255, 255, 255, 0.55);
            font-size: 0.88rem;
            padding: 4px 0;
            transition: color var(--transition);
        }
        .site-footer .footer-col a:hover {
            color: var(--secondary-light);
        }
        .site-footer .footer-bottom {
            border-top: 1px solid rgba(255, 255, 255, 0.06);
            padding-top: 24px;
            display: flex;
            flex-wrap: wrap;
            justify-content: space-between;
            align-items: center;
            gap: 12px;
            font-size: 0.82rem;
            color: rgba(255, 255, 255, 0.4);
        }

        /* ===== Responsive ===== */
        @media (max-width: 1024px) {
            .site-footer .footer-grid {
                grid-template-columns: 1fr 1fr;
                gap: 32px;
            }
            .nav-search {
                max-width: 280px;
            }
        }
        @media (max-width: 820px) {
            .nav-search {
                max-width: 200px;
            }
            .nav-actions .btn-ghost {
                display: none;
            }
            .card-grid {
                grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
            }
            .features-grid {
                grid-template-columns: 1fr 1fr;
            }
        }
        @media (max-width: 768px) {
            :root {
                --nav-height: 64px;
            }
            .mobile-toggle {
                display: block;
            }
            .nav-links,
            .nav-search,
            .nav-actions {
                display: none;
            }
            .nav-links.open,
            .nav-search.open,
            .nav-actions.open {
                display: flex;
            }
            .nav-links.open {
                position: absolute;
                top: var(--nav-height);
                left: 0;
                right: 0;
                background: rgba(255, 255, 255, 0.98);
                backdrop-filter: blur(16px);
                flex-direction: column;
                padding: 16px 24px 24px;
                border-bottom: 1px solid var(--border);
                box-shadow: var(--shadow-lg);
                gap: 6px;
                border-radius: 0 0 var(--radius) var(--radius);
            }
            .nav-links.open a {
                padding: 12px 20px;
                width: 100%;
                border-radius: var(--radius-sm);
            }
            .nav-search.open {
                position: absolute;
                top: calc(var(--nav-height) + 140px);
                left: 0;
                right: 0;
                padding: 0 24px 20px;
                background: rgba(255, 255, 255, 0.98);
                max-width: 100%;
            }
            .nav-actions.open {
                position: absolute;
                top: calc(var(--nav-height) + 200px);
                left: 0;
                right: 0;
                padding: 0 24px 24px;
                background: rgba(255, 255, 255, 0.98);
                gap: 12px;
                flex-wrap: wrap;
            }
            .nav-actions.open .btn-ghost {
                display: inline-block;
            }
            .page-hero {
                padding: 70px 0 60px;
                min-height: 280px;
            }
            .page-hero h1 {
                font-size: 1.8rem;
            }
            .page-hero p {
                font-size: 1rem;
            }
            .section {
                padding: 56px 0;
            }
            .section-header {
                margin-bottom: 36px;
            }
            .card-grid {
                grid-template-columns: 1fr;
                gap: 20px;
            }
            .steps-grid {
                grid-template-columns: 1fr 1fr;
                gap: 20px;
            }
            .features-grid {
                grid-template-columns: 1fr;
            }
            .stats-grid {
                grid-template-columns: 1fr 1fr;
                gap: 20px;
            }
            .site-footer .footer-grid {
                grid-template-columns: 1fr;
                gap: 28px;
            }
            .site-footer .footer-bottom {
                flex-direction: column;
                text-align: center;
            }
            .cta-section {
                padding: 56px 0;
            }
            .cta-section .btn-cta {
                padding: 14px 32px;
                font-size: 0.95rem;
            }
            .faq-item .faq-q {
                padding: 16px 18px;
                font-size: 0.95rem;
            }
        }
        @media (max-width: 520px) {
            .container {
                padding: 0 16px;
            }
            .page-hero {
                padding: 50px 0 44px;
                min-height: 220px;
            }
            .page-hero h1 {
                font-size: 1.5rem;
            }
            .page-hero .hero-tags .tag {
                font-size: 0.7rem;
                padding: 4px 14px;
            }
            .section {
                padding: 40px 0;
            }
            .card {
                padding: 20px 16px;
            }
            .steps-grid {
                grid-template-columns: 1fr;
                gap: 16px;
            }
            .stats-grid {
                grid-template-columns: 1fr 1fr;
                gap: 16px;
            }
            .stat-item .stat-number {
                font-size: 1.8rem;
            }
            .logo {
                font-size: 1.1rem;
            }
            .logo i {
                font-size: 1.2rem;
            }
        }

        /* ===== Utility ===== */
        .text-center {
            text-align: center;
        }
        .mt-8 {
            margin-top: 8px;
        }
        .mt-16 {
            margin-top: 16px;
        }
        .mt-24 {
            margin-top: 24px;
        }
        .mt-32 {
            margin-top: 32px;
        }
        .gap-8 {
            gap: 8px;
        }
        .flex-center {
            display: flex;
            align-items: center;
            justify-content: center;
        }

        /* ===== Print ===== */
        @media print {
            .site-header {
                position: static;
                box-shadow: none;
            }
            .nav-search,
            .nav-actions,
            .mobile-toggle {
                display: none !important;
            }
            .page-hero {
                padding: 40px 0;
                min-height: auto;
                background: #f8fafc;
            }
            .page-hero h1 {
                color: #1e293b;
            }
            .page-hero p {
                color: #64748b;
            }
            .cta-section {
                background: #f1f5f9 !important;
            }
            .cta-section h2 {
                color: #1e293b;
            }
            .cta-section p {
                color: #64748b;
            }
            .cta-section .btn-cta {
                color: #fff;
                background: var(--primary);
            }
            .card:hover {
                transform: none;
                box-shadow: var(--shadow);
            }
        }

/* roulang page: article */
/* ===== Design Variables ===== */
        :root {
            --primary: #6366f1;
            --primary-dark: #4f46e5;
            --primary-light: #a5b4fc;
            --secondary: #f59e0b;
            --secondary-light: #fbbf24;
            --accent: #06b6d4;
            --bg-light: #f8fafc;
            --bg-dark: #0f172a;
            --bg-card: #ffffff;
            --text-main: #1e293b;
            --text-secondary: #64748b;
            --text-light: #94a3b8;
            --text-white: #f1f5f9;
            --border: #e2e8f0;
            --border-light: #f1f5f9;
            --radius-sm: 8px;
            --radius-md: 16px;
            --radius-lg: 24px;
            --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
            --shadow-md: 0 4px 20px rgba(0,0,0,0.08);
            --shadow-lg: 0 12px 40px rgba(0,0,0,0.12);
            --shadow-xl: 0 20px 60px rgba(0,0,0,0.18);
            --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
            --space-xs: 8px;
            --space-sm: 16px;
            --space-md: 32px;
            --space-lg: 64px;
            --space-xl: 100px;
            --max-width: 1200px;
            --font-sans: 'Segoe UI', system-ui, -apple-system, BlinkMacSystemFont, 'Helvetica Neue', Arial, sans-serif;
        }

        /* ===== Reset & Base ===== */
        *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
        html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }
        body {
            font-family: var(--font-sans);
            font-size: 16px;
            line-height: 1.7;
            color: var(--text-main);
            background: var(--bg-light);
        }
        a { color: var(--primary); text-decoration: none; transition: var(--transition); }
        a:hover { color: var(--primary-dark); }
        img { max-width: 100%; height: auto; display: block; border-radius: var(--radius-sm); }
        ul, ol { list-style: none; }
        button, input, textarea { font-family: inherit; font-size: inherit; outline: none; border: none; }
        .container {
            max-width: var(--max-width);
            margin: 0 auto;
            padding: 0 24px;
        }
        .container-narrow {
            max-width: 820px;
            margin: 0 auto;
            padding: 0 24px;
        }
        .section-title {
            font-size: 2rem;
            font-weight: 800;
            color: var(--text-main);
            margin-bottom: 0.5rem;
            letter-spacing: -0.02em;
        }
        .section-subtitle {
            font-size: 1.1rem;
            color: var(--text-secondary);
            margin-bottom: var(--space-md);
            max-width: 600px;
        }
        .text-center { text-align: center; }
        .mx-auto { margin-left: auto; margin-right: auto; }

        /* ===== Buttons ===== */
        .btn {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 12px 28px;
            border-radius: 50px;
            font-weight: 600;
            font-size: 0.95rem;
            cursor: pointer;
            transition: var(--transition);
            border: 2px solid transparent;
            background: transparent;
            color: var(--text-main);
        }
        .btn-primary {
            background: var(--primary);
            color: #fff;
            border-color: var(--primary);
        }
        .btn-primary:hover {
            background: var(--primary-dark);
            border-color: var(--primary-dark);
            transform: translateY(-2px);
            box-shadow: 0 8px 25px rgba(99,102,241,0.35);
            color: #fff;
        }
        .btn-secondary {
            background: var(--secondary);
            color: #1e293b;
            border-color: var(--secondary);
        }
        .btn-secondary:hover {
            background: var(--secondary-light);
            border-color: var(--secondary-light);
            transform: translateY(-2px);
            box-shadow: 0 8px 25px rgba(245,158,11,0.35);
            color: #1e293b;
        }
        .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-light);
            transform: translateY(-2px);
            box-shadow: 0 8px 25px rgba(0,0,0,0.1);
            color: var(--primary-dark);
        }
        .btn-sm {
            padding: 8px 18px;
            font-size: 0.85rem;
        }
        .btn-lg {
            padding: 16px 36px;
            font-size: 1.05rem;
        }

        /* ===== Badge / Tag ===== */
        .badge {
            display: inline-block;
            padding: 4px 14px;
            border-radius: 50px;
            font-size: 0.8rem;
            font-weight: 600;
            background: var(--primary-light);
            color: var(--primary-dark);
            transition: var(--transition);
        }
        .badge-secondary {
            background: #fef3c7;
            color: #92400e;
        }
        .badge-accent {
            background: #cffafe;
            color: #0e7490;
        }

        /* ===== Header & Navigation ===== */
        .site-header {
            position: sticky;
            top: 0;
            z-index: 1000;
            background: rgba(255,255,255,0.92);
            backdrop-filter: blur(18px);
            -webkit-backdrop-filter: blur(18px);
            border-bottom: 1px solid var(--border);
            box-shadow: 0 1px 8px rgba(0,0,0,0.04);
        }
        .header-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            height: 72px;
            gap: 20px;
        }
        .logo {
            display: flex;
            align-items: center;
            gap: 10px;
            font-size: 1.35rem;
            font-weight: 800;
            color: var(--text-main);
            letter-spacing: -0.03em;
            white-space: nowrap;
        }
        .logo i {
            color: var(--primary);
            font-size: 1.5rem;
        }
        .logo:hover { color: var(--primary); }
        .nav-links {
            display: flex;
            align-items: center;
            gap: 6px;
        }
        .nav-links a {
            padding: 8px 18px;
            border-radius: 50px;
            font-weight: 500;
            font-size: 0.95rem;
            color: var(--text-secondary);
            transition: var(--transition);
            position: relative;
        }
        .nav-links a:hover {
            color: var(--primary);
            background: rgba(99,102,241,0.08);
        }
        .nav-links a.active {
            color: #fff;
            background: var(--primary);
            box-shadow: 0 4px 12px rgba(99,102,241,0.3);
        }
        .nav-links a.active:hover {
            color: #fff;
            background: var(--primary-dark);
        }
        .header-search {
            display: flex;
            align-items: center;
            background: var(--bg-light);
            border-radius: 50px;
            padding: 0 16px;
            border: 1px solid var(--border);
            transition: var(--transition);
            flex: 1;
            max-width: 320px;
            min-width: 160px;
        }
        .header-search:focus-within {
            border-color: var(--primary);
            box-shadow: 0 0 0 4px rgba(99,102,241,0.12);
            background: #fff;
        }
        .header-search i {
            color: var(--text-light);
            font-size: 0.9rem;
        }
        .header-search input {
            background: transparent;
            border: none;
            padding: 10px 12px;
            font-size: 0.9rem;
            color: var(--text-main);
            width: 100%;
        }
        .header-search input::placeholder {
            color: var(--text-light);
        }
        .menu-toggle {
            display: none;
            background: none;
            font-size: 1.5rem;
            color: var(--text-main);
            cursor: pointer;
            padding: 4px 8px;
            border-radius: var(--radius-sm);
            transition: var(--transition);
        }
        .menu-toggle:hover {
            background: var(--bg-light);
        }

        /* ===== Article Hero ===== */
        .article-hero {
            position: relative;
            padding: var(--space-lg) 0 var(--space-md);
            background: linear-gradient(135deg, #0f172a 0%, #1e293b 50%, #0f172a 100%);
            min-height: 320px;
            display: flex;
            align-items: center;
            overflow: hidden;
        }
        .article-hero::before {
            content: '';
            position: absolute;
            inset: 0;
            background: url('/assets/images/backpic/back-2.png') center/cover no-repeat;
            opacity: 0.18;
            z-index: 0;
        }
        .article-hero .container-narrow {
            position: relative;
            z-index: 1;
        }
        .article-hero .badge {
            margin-bottom: var(--space-sm);
            display: inline-block;
        }
        .article-hero h1 {
            font-size: 2.6rem;
            font-weight: 800;
            color: #fff;
            line-height: 1.2;
            letter-spacing: -0.02em;
            margin-bottom: var(--space-sm);
            max-width: 800px;
        }
        .article-meta {
            display: flex;
            flex-wrap: wrap;
            align-items: center;
            gap: 16px 24px;
            color: rgba(255,255,255,0.7);
            font-size: 0.9rem;
        }
        .article-meta i {
            margin-right: 6px;
            color: var(--primary-light);
        }
        .article-meta span {
            display: flex;
            align-items: center;
        }

        /* ===== Article Content ===== */
        .article-main {
            padding: var(--space-lg) 0 var(--space-xl);
        }
        .article-body {
            background: var(--bg-card);
            border-radius: var(--radius-md);
            padding: var(--space-md) var(--space-md);
            box-shadow: var(--shadow-sm);
            border: 1px solid var(--border-light);
        }
        .article-body img {
            border-radius: var(--radius-md);
            margin: var(--space-sm) 0;
            width: 100%;
            object-fit: cover;
        }
        .article-body p {
            margin-bottom: 1.2rem;
            color: var(--text-main);
            line-height: 1.8;
        }
        .article-body h2 {
            font-size: 1.6rem;
            font-weight: 700;
            margin: var(--space-md) 0 var(--space-sm);
            color: var(--text-main);
        }
        .article-body h3 {
            font-size: 1.25rem;
            font-weight: 600;
            margin: var(--space-sm) 0 var(--space-xs);
            color: var(--text-main);
        }
        .article-body ul, .article-body ol {
            margin-bottom: 1.2rem;
            padding-left: 24px;
        }
        .article-body ul li {
            list-style: disc;
            margin-bottom: 6px;
            color: var(--text-secondary);
        }
        .article-body ol li {
            list-style: decimal;
            margin-bottom: 6px;
            color: var(--text-secondary);
        }
        .article-body blockquote {
            border-left: 4px solid var(--primary);
            padding: var(--space-xs) var(--space-sm);
            margin: var(--space-sm) 0;
            background: rgba(99,102,241,0.05);
            border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
            color: var(--text-secondary);
            font-style: italic;
        }
        .article-body a {
            color: var(--primary);
            text-decoration: underline;
            text-underline-offset: 2px;
        }
        .article-body a:hover {
            color: var(--primary-dark);
        }
        .article-not-found {
            text-align: center;
            padding: var(--space-xl) 0;
        }
        .article-not-found i {
            font-size: 4rem;
            color: var(--text-light);
            margin-bottom: var(--space-sm);
        }
        .article-not-found h2 {
            font-size: 1.8rem;
            color: var(--text-main);
            margin-bottom: var(--space-xs);
        }
        .article-not-found p {
            color: var(--text-secondary);
            margin-bottom: var(--space-sm);
        }

        /* ===== Related Posts ===== */
        .related-section {
            padding: var(--space-lg) 0;
            background: var(--bg-light);
        }
        .related-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 24px;
            margin-top: var(--space-md);
        }
        .related-card {
            background: var(--bg-card);
            border-radius: var(--radius-md);
            overflow: hidden;
            border: 1px solid var(--border);
            transition: var(--transition);
            box-shadow: var(--shadow-sm);
        }
        .related-card:hover {
            transform: translateY(-6px);
            box-shadow: var(--shadow-lg);
            border-color: transparent;
        }
        .related-card img {
            width: 100%;
            height: 180px;
            object-fit: cover;
            border-radius: 0;
        }
        .related-card-body {
            padding: 18px 20px 22px;
        }
        .related-card-body .badge {
            margin-bottom: 8px;
        }
        .related-card-body h3 {
            font-size: 1.05rem;
            font-weight: 700;
            color: var(--text-main);
            line-height: 1.4;
            margin-bottom: 6px;
            display: -webkit-box;
            -webkit-line-clamp: 2;
            -webkit-box-orient: vertical;
            overflow: hidden;
        }
        .related-card-body p {
            font-size: 0.88rem;
            color: var(--text-secondary);
            display: -webkit-box;
            -webkit-line-clamp: 2;
            -webkit-box-orient: vertical;
            overflow: hidden;
        }
        .related-card-body .meta {
            font-size: 0.8rem;
            color: var(--text-light);
            margin-top: 10px;
            display: flex;
            align-items: center;
            gap: 12px;
        }

        /* ===== CTA Section ===== */
        .cta-section {
            padding: var(--space-lg) 0;
            background: linear-gradient(135deg, var(--primary) 0%, #4f46e5 100%);
            position: relative;
            overflow: hidden;
        }
        .cta-section::before {
            content: '';
            position: absolute;
            inset: 0;
            background: url('/assets/images/backpic/back-3.png') center/cover no-repeat;
            opacity: 0.08;
            z-index: 0;
        }
        .cta-section .container {
            position: relative;
            z-index: 1;
            text-align: center;
        }
        .cta-section h2 {
            font-size: 2.2rem;
            font-weight: 800;
            color: #fff;
            margin-bottom: 0.5rem;
        }
        .cta-section p {
            font-size: 1.1rem;
            color: rgba(255,255,255,0.85);
            max-width: 600px;
            margin: 0 auto var(--space-sm);
        }
        .cta-buttons {
            display: flex;
            justify-content: center;
            gap: 16px;
            flex-wrap: wrap;
            margin-top: var(--space-sm);
        }

        /* ===== Footer ===== */
        .site-footer {
            background: var(--bg-dark);
            color: rgba(255,255,255,0.7);
            padding: var(--space-lg) 0 0;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr 1fr;
            gap: 40px;
            padding-bottom: var(--space-md);
            border-bottom: 1px solid rgba(255,255,255,0.08);
        }
        .footer-brand .logo {
            color: #fff;
            font-size: 1.4rem;
            margin-bottom: var(--space-xs);
        }
        .footer-brand .logo i {
            color: var(--primary-light);
        }
        .footer-brand p {
            font-size: 0.92rem;
            color: rgba(255,255,255,0.55);
            max-width: 320px;
            line-height: 1.7;
        }
        .footer-col h4 {
            font-size: 1rem;
            font-weight: 700;
            color: #fff;
            margin-bottom: var(--space-sm);
            letter-spacing: 0.02em;
        }
        .footer-col a {
            display: block;
            color: rgba(255,255,255,0.55);
            font-size: 0.9rem;
            padding: 4px 0;
            transition: var(--transition);
        }
        .footer-col a:hover {
            color: var(--primary-light);
            padding-left: 4px;
        }
        .footer-bottom {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 20px 0;
            font-size: 0.85rem;
            color: rgba(255,255,255,0.35);
            flex-wrap: wrap;
            gap: 8px;
        }

        /* ===== Responsive ===== */
        @media (max-width: 1024px) {
            .footer-grid {
                grid-template-columns: 1fr 1fr;
                gap: 32px;
            }
            .related-grid {
                grid-template-columns: repeat(2, 1fr);
            }
        }

        @media (max-width: 768px) {
            .header-inner {
                height: 64px;
            }
            .nav-links {
                display: none;
                position: absolute;
                top: 64px;
                left: 0;
                right: 0;
                background: rgba(255,255,255,0.98);
                backdrop-filter: blur(18px);
                flex-direction: column;
                padding: 16px 24px;
                border-bottom: 1px solid var(--border);
                box-shadow: var(--shadow-md);
                gap: 4px;
            }
            .nav-links.open {
                display: flex;
            }
            .nav-links a {
                padding: 12px 16px;
                width: 100%;
                border-radius: var(--radius-sm);
            }
            .menu-toggle {
                display: block;
            }
            .header-search {
                max-width: 180px;
                min-width: 120px;
            }
            .header-search input {
                padding: 8px 10px;
                font-size: 0.85rem;
            }
            .article-hero h1 {
                font-size: 1.8rem;
            }
            .article-hero {
                min-height: 240px;
                padding: var(--space-md) 0;
            }
            .section-title {
                font-size: 1.6rem;
            }
            .related-grid {
                grid-template-columns: 1fr;
            }
            .footer-grid {
                grid-template-columns: 1fr;
                gap: 24px;
            }
            .footer-bottom {
                flex-direction: column;
                text-align: center;
            }
            .article-body {
                padding: var(--space-sm);
            }
            .cta-section h2 {
                font-size: 1.6rem;
            }
        }

        @media (max-width: 520px) {
            .header-search {
                max-width: 120px;
                min-width: 80px;
            }
            .header-search input {
                padding: 6px 8px;
                font-size: 0.8rem;
            }
            .header-search {
                padding: 0 10px;
            }
            .logo {
                font-size: 1.1rem;
            }
            .logo i {
                font-size: 1.2rem;
            }
            .article-hero h1 {
                font-size: 1.4rem;
            }
            .article-meta {
                font-size: 0.8rem;
                gap: 8px 16px;
            }
            .section-title {
                font-size: 1.3rem;
            }
            .btn-lg {
                padding: 12px 24px;
                font-size: 0.9rem;
            }
            .container {
                padding: 0 16px;
            }
            .container-narrow {
                padding: 0 16px;
            }
        }

        /* ===== Accessibility ===== */
        a:focus-visible, button:focus-visible, input:focus-visible {
            outline: 3px solid var(--primary-light);
            outline-offset: 2px;
        }
        @media (prefers-reduced-motion: reduce) {
            *, *::before, *::after {
                transition: none !important;
                animation: none !important;
            }
        }