/* roulang page: index */
:root {
            --primary: #4F46E5;
            --primary-dark: #4338CA;
            --secondary: #0EA5E9;
            --accent: #7C3AED;
            --bg-light: #F8FAFC;
            --bg-white: #FFFFFF;
            --text-dark: #0F172A;
            --text-muted: #64748B;
            --border-color: #E2E8F0;
            --radius-sm: 6px;
            --radius-md: 12px;
            --radius-lg: 20px;
            --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);
            --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        }
        * { box-sizing: border-box; margin: 0; padding: 0; }
        body {
            font-family: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
            background: var(--bg-light);
            color: var(--text-dark);
            line-height: 1.6;
            -webkit-font-smoothing: antialiased;
        }
        .container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
        a { color: inherit; text-decoration: none; transition: var(--transition); }
        img { max-width: 100%; height: auto; display: block; }
        button, input, textarea { font-family: inherit; font-size: inherit; outline: none; border: none; }
        .gradient-text {
            background: linear-gradient(135deg, var(--primary), var(--secondary));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        .gradient-bg {
            background: linear-gradient(135deg, var(--primary), var(--accent));
        }
        .gradient-bg-secondary {
            background: linear-gradient(135deg, var(--secondary), var(--primary));
        }
        .btn {
            display: inline-flex; align-items: center; gap: 8px;
            padding: 12px 28px; border-radius: 9999px; font-weight: 600;
            transition: var(--transition); cursor: pointer; border: none;
            font-size: 1rem; line-height: 1.4;
        }
        .btn-primary {
            background: linear-gradient(135deg, var(--primary), var(--accent));
            color: #fff; box-shadow: 0 4px 16px rgba(79,70,229,0.35);
        }
        .btn-primary:hover {
            transform: translateY(-2px); box-shadow: 0 8px 28px rgba(79,70,229,0.45);
        }
        .btn-primary:active { transform: translateY(0); }
        .btn-primary:focus-visible { outline: 3px solid var(--secondary); outline-offset: 2px; }
        .btn-outline {
            background: transparent; color: var(--primary); border: 2px solid var(--primary);
        }
        .btn-outline:hover {
            background: var(--primary); color: #fff; transform: translateY(-2px);
        }
        .btn-outline:focus-visible { outline: 3px solid var(--secondary); outline-offset: 2px; }
        .card {
            background: var(--bg-white); border-radius: var(--radius-md);
            box-shadow: var(--shadow-sm); transition: var(--transition);
            border: 1px solid var(--border-color); overflow: hidden;
        }
        .card:hover {
            box-shadow: var(--shadow-md); transform: translateY(-4px);
        }
        .badge {
            display: inline-block; padding: 4px 14px; border-radius: 9999px;
            font-size: 0.75rem; font-weight: 600; letter-spacing: 0.3px;
            background: rgba(79,70,229,0.1); color: var(--primary);
        }
        .badge-secondary {
            background: rgba(14,165,233,0.1); color: var(--secondary);
        }
        .badge-accent {
            background: rgba(124,58,237,0.1); color: var(--accent);
        }
        .section-title {
            font-size: 2rem; font-weight: 800; line-height: 1.3; margin-bottom: 12px;
        }
        .section-subtitle {
            color: var(--text-muted); font-size: 1.1rem; max-width: 640px; margin: 0 auto 48px;
        }
        .text-balance { text-wrap: balance; }
        /* Header */
        .site-header {
            background: rgba(255,255,255,0.95); backdrop-filter: blur(12px);
            border-bottom: 1px solid var(--border-color);
            position: sticky; top: 0; z-index: 100; transition: var(--transition);
        }
        .site-header.scrolled { box-shadow: var(--shadow-md); }
        .nav-link {
            position: relative; padding: 8px 0; font-weight: 500; color: var(--text-muted);
            transition: var(--transition); font-size: 0.95rem;
        }
        .nav-link::after {
            content: ''; position: absolute; bottom: 0; left: 0; width: 0; height: 2px;
            background: var(--primary); transition: var(--transition); border-radius: 2px;
        }
        .nav-link:hover { color: var(--text-dark); }
        .nav-link:hover::after { width: 100%; }
        .nav-link.active { color: var(--primary); }
        .nav-link.active::after { width: 100%; }
        .search-box {
            display: flex; align-items: center; background: var(--bg-light);
            border-radius: 9999px; padding: 6px 6px 6px 18px;
            border: 1px solid var(--border-color); transition: var(--transition);
        }
        .search-box:focus-within {
            border-color: var(--primary); box-shadow: 0 0 0 3px rgba(79,70,229,0.15);
        }
        .search-box input {
            background: transparent; border: none; outline: none; padding: 6px 0;
            font-size: 0.9rem; color: var(--text-dark); width: 140px;
        }
        .search-box input::placeholder { color: var(--text-muted); }
        .search-box button {
            background: var(--primary); color: #fff; border-radius: 9999px;
            padding: 8px 16px; font-size: 0.85rem; font-weight: 600; cursor: pointer;
            transition: var(--transition); border: none;
        }
        .search-box button:hover { background: var(--primary-dark); }
        /* Hero */
        .hero {
            padding: 80px 0 100px; position: relative; overflow: hidden;
            background: linear-gradient(135deg, #EEF2FF 0%, #E0F2FE 50%, #F3E8FF 100%);
        }
        .hero::before {
            content: ''; position: absolute; top: -30%; right: -10%; width: 500px; height: 500px;
            background: radial-gradient(circle, rgba(79,70,229,0.08) 0%, transparent 70%);
            border-radius: 50%; pointer-events: none;
        }
        .hero::after {
            content: ''; position: absolute; bottom: -20%; left: -10%; width: 400px; height: 400px;
            background: radial-gradient(circle, rgba(14,165,233,0.08) 0%, transparent 70%);
            border-radius: 50%; pointer-events: none;
        }
        .hero-content { position: relative; z-index: 1; }
        .hero h1 { font-size: 3.2rem; font-weight: 900; line-height: 1.15; margin-bottom: 20px; }
        .hero p { font-size: 1.2rem; color: var(--text-muted); max-width: 560px; margin-bottom: 36px; }
        .hero-stats { display: flex; gap: 40px; margin-top: 48px; flex-wrap: wrap; }
        .hero-stat h3 { font-size: 2rem; font-weight: 800; }
        .hero-stat p { font-size: 0.9rem; margin-bottom: 0; color: var(--text-muted); }
        /* Feature grid */
        .feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
        .feature-card { padding: 32px 24px; text-align: center; }
        .feature-card .icon { font-size: 2.4rem; margin-bottom: 16px; color: var(--primary); }
        .feature-card h3 { font-size: 1.2rem; font-weight: 700; margin-bottom: 8px; }
        .feature-card p { font-size: 0.95rem; color: var(--text-muted); }
        /* Content cards */
        .content-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
        .content-card { padding: 24px; }
        .content-card .meta { display: flex; gap: 16px; font-size: 0.85rem; color: var(--text-muted); margin-bottom: 8px; }
        .content-card h3 { font-size: 1.15rem; font-weight: 700; margin-bottom: 8px; line-height: 1.4; }
        .content-card h3 a { color: var(--text-dark); }
        .content-card h3 a:hover { color: var(--primary); }
        .content-card p { font-size: 0.95rem; color: var(--text-muted); }
        .content-card .tags { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 12px; }
        /* Process */
        .process-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
        .process-step { text-align: center; position: relative; }
        .process-step .step-number {
            width: 56px; height: 56px; border-radius: 50%;
            background: linear-gradient(135deg, var(--primary), var(--accent));
            color: #fff; font-size: 1.4rem; font-weight: 800;
            display: flex; align-items: center; justify-content: center; margin: 0 auto 16px;
            box-shadow: 0 4px 16px rgba(79,70,229,0.3);
        }
        .process-step h4 { font-size: 1.05rem; font-weight: 700; margin-bottom: 6px; }
        .process-step p { font-size: 0.9rem; color: var(--text-muted); }
        .process-step::after {
            content: '→'; position: absolute; top: 24px; right: -16px;
            font-size: 1.5rem; color: var(--border-color); font-weight: 300;
        }
        .process-step:last-child::after { display: none; }
        /* FAQ */
        .faq-item {
            border-bottom: 1px solid var(--border-color); padding: 20px 0; cursor: pointer;
        }
        .faq-item:first-child { padding-top: 0; }
        .faq-question {
            display: flex; justify-content: space-between; align-items: center;
            font-size: 1.05rem; font-weight: 600; gap: 16px;
        }
        .faq-question i { transition: var(--transition); color: var(--text-muted); font-size: 1.2rem; }
        .faq-item.open .faq-question i { transform: rotate(180deg); color: var(--primary); }
        .faq-answer {
            max-height: 0; overflow: hidden; transition: max-height 0.4s ease, padding 0.3s ease;
            color: var(--text-muted); font-size: 0.95rem; line-height: 1.7;
        }
        .faq-item.open .faq-answer { max-height: 300px; padding-top: 12px; }
        /* CTA */
        .cta-section {
            padding: 80px 0; text-align: center;
            background: linear-gradient(135deg, var(--primary), var(--accent));
            color: #fff; border-radius: var(--radius-lg);
        }
        .cta-section h2 { font-size: 2.2rem; font-weight: 800; margin-bottom: 16px; }
        .cta-section p { font-size: 1.1rem; opacity: 0.9; max-width: 520px; margin: 0 auto 32px; }
        .cta-section .btn { background: #fff; color: var(--primary); box-shadow: 0 4px 20px rgba(0,0,0,0.15); }
        .cta-section .btn:hover { transform: translateY(-2px); box-shadow: 0 8px 32px rgba(0,0,0,0.2); }
        /* Footer */
        .site-footer {
            padding: 48px 0 24px; background: var(--bg-white); border-top: 1px solid var(--border-color);
        }
        .footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; }
        .footer-brand .logo { font-size: 1.4rem; font-weight: 800; margin-bottom: 12px; }
        .footer-brand p { color: var(--text-muted); font-size: 0.9rem; max-width: 300px; }
        .footer-col h4 { font-size: 0.95rem; font-weight: 700; margin-bottom: 16px; text-transform: uppercase; letter-spacing: 0.5px; }
        .footer-col a { display: block; color: var(--text-muted); font-size: 0.9rem; padding: 4px 0; }
        .footer-col a:hover { color: var(--primary); }
        .footer-bottom { margin-top: 32px; padding-top: 20px; border-top: 1px solid var(--border-color); text-align: center; color: var(--text-muted); font-size: 0.85rem; }
        /* Category page */
        .category-hero { padding: 60px 0 64px; background: linear-gradient(135deg, #EEF2FF, #E0F2FE); }
        .category-hero h1 { font-size: 2.6rem; font-weight: 900; }
        .category-hero p { font-size: 1.1rem; color: var(--text-muted); max-width: 560px; }
        /* Article page */
        .article-header { padding: 48px 0 24px; }
        .article-header h1 { font-size: 2.4rem; font-weight: 800; line-height: 1.3; }
        .article-meta { display: flex; gap: 20px; color: var(--text-muted); font-size: 0.9rem; margin-top: 12px; flex-wrap: wrap; }
        .article-body { max-width: 800px; margin: 0 auto; padding: 32px 0 64px; }
        .article-body p { margin-bottom: 20px; font-size: 1.05rem; line-height: 1.8; color: #334155; }
        .article-body h2 { font-size: 1.6rem; font-weight: 700; margin: 40px 0 16px; }
        .article-body h3 { font-size: 1.25rem; font-weight: 700; margin: 28px 0 12px; }
        .article-body ul, .article-body ol { margin: 16px 0; padding-left: 24px; color: #334155; }
        .article-body li { margin-bottom: 8px; font-size: 1.05rem; line-height: 1.7; }
        .article-body img { border-radius: var(--radius-md); margin: 24px 0; box-shadow: var(--shadow-sm); }
        .article-body blockquote {
            border-left: 4px solid var(--primary); padding: 16px 24px; margin: 24px 0;
            background: rgba(79,70,229,0.04); border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
            font-style: italic; color: #475569;
        }
        /* Not found */
        .not-found { text-align: center; padding: 80px 20px; }
        .not-found h2 { font-size: 2rem; margin-bottom: 16px; }
        .not-found p { color: var(--text-muted); margin-bottom: 24px; }
        /* Mobile nav */
        .mobile-nav-toggle { display: none; flex-direction: column; gap: 5px; cursor: pointer; padding: 8px; background: none; border: none; }
        .mobile-nav-toggle span { width: 26px; height: 2px; background: var(--text-dark); border-radius: 2px; transition: var(--transition); }
        .mobile-nav-toggle.open span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
        .mobile-nav-toggle.open span:nth-child(2) { opacity: 0; }
        .mobile-nav-toggle.open span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }
        /* Responsive */
        @media (max-width: 1024px) {
            .feature-grid { grid-template-columns: repeat(2, 1fr); }
            .process-grid { grid-template-columns: repeat(2, 1fr); }
            .process-step:nth-child(2)::after { display: none; }
            .footer-grid { grid-template-columns: 1fr 1fr; }
            .hero h1 { font-size: 2.6rem; }
        }
        @media (max-width: 768px) {
            .container { padding: 0 20px; }
            .nav-links { display: none; }
            .nav-links.open { display: flex; flex-direction: column; position: absolute; top: 100%; left: 0; right: 0; background: var(--bg-white); border-bottom: 1px solid var(--border-color); padding: 16px 24px; gap: 12px; box-shadow: var(--shadow-md); }
            .mobile-nav-toggle { display: flex; }
            .search-box { display: none; }
            .search-box.mobile-show { display: flex; margin-top: 12px; }
            .hero { padding: 48px 0 64px; }
            .hero h1 { font-size: 2rem; }
            .hero p { font-size: 1rem; }
            .hero-stats { gap: 24px; }
            .hero-stat h3 { font-size: 1.6rem; }
            .feature-grid { grid-template-columns: 1fr; }
            .content-grid { grid-template-columns: 1fr; }
            .process-grid { grid-template-columns: 1fr; }
            .process-step::after { display: none; }
            .footer-grid { grid-template-columns: 1fr; gap: 24px; }
            .section-title { font-size: 1.6rem; }
            .cta-section { padding: 48px 24px; border-radius: var(--radius-md); }
            .cta-section h2 { font-size: 1.6rem; }
            .category-hero h1 { font-size: 1.8rem; }
            .article-header h1 { font-size: 1.6rem; }
            .article-body p { font-size: 1rem; }
        }
        @media (max-width: 520px) {
            .hero h1 { font-size: 1.6rem; }
            .hero-stat { min-width: 100px; }
            .hero-stats { gap: 16px; }
            .btn { padding: 10px 20px; font-size: 0.9rem; }
            .content-card { padding: 16px; }
            .feature-card { padding: 24px 16px; }
        }
        /* Animations */
        .fade-up { opacity: 0; transform: translateY(30px); transition: opacity 0.6s ease, transform 0.6s ease; }
        .fade-up.visible { opacity: 1; transform: translateY(0); }
        /* Scrollbar */
        ::-webkit-scrollbar { width: 8px; }
        ::-webkit-scrollbar-track { background: var(--bg-light); }
        ::-webkit-scrollbar-thumb { background: #CBD5E1; border-radius: 4px; }
        ::-webkit-scrollbar-thumb:hover { background: #94A3B8; }

/* roulang page: article */
/* ===== Design Variables ===== */
        :root {
            --primary: #4f46e5;
            --primary-light: #6366f1;
            --primary-dark: #3730a3;
            --primary-bg: #eef2ff;
            --secondary: #0ea5e9;
            --secondary-light: #38bdf8;
            --accent: #f59e0b;
            --bg: #ffffff;
            --bg-alt: #f8fafc;
            --bg-card: #ffffff;
            --text: #0f172a;
            --text-secondary: #475569;
            --text-muted: #94a3b8;
            --border: #e2e8f0;
            --border-light: #f1f5f9;
            --radius: 16px;
            --radius-sm: 10px;
            --radius-xs: 6px;
            --shadow: 0 4px 24px rgba(79, 70, 229, 0.08);
            --shadow-hover: 0 12px 40px rgba(79, 70, 229, 0.14);
            --shadow-card: 0 2px 16px rgba(0, 0, 0, 0.06);
            --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
            --font: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'PingFang SC', 'Microsoft YaHei', 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: 1.7;
            color: var(--text);
            background: var(--bg);
            overflow-x: hidden;
        }
        img { max-width: 100%; height: auto; display: block; }
        a { color: inherit; text-decoration: none; transition: var(--transition); }
        button { font-family: inherit; cursor: pointer; border: none; background: none; }
        input, textarea { font-family: inherit; font-size: inherit; }
        ul, ol { list-style: none; }
        h1, h2, h3, h4, h5, h6 { line-height: 1.3; font-weight: 700; color: var(--text); }

        /* ===== Container ===== */
        .container {
            max-width: var(--container);
            margin: 0 auto;
            padding: 0 24px;
        }

        /* ===== Utility ===== */
        .flex { display: flex; }
        .flex-col { flex-direction: column; }
        .items-center { align-items: center; }
        .justify-between { justify-content: space-between; }
        .justify-center { justify-content: center; }
        .flex-wrap { flex-wrap: wrap; }
        .gap-2 { gap: 8px; }
        .gap-3 { gap: 12px; }
        .gap-4 { gap: 16px; }
        .gap-6 { gap: 24px; }
        .gap-8 { gap: 32px; }
        .gap-12 { gap: 48px; }
        .text-center { text-align: center; }
        .text-muted { color: var(--text-muted); }
        .gradient-text {
            background: linear-gradient(135deg, var(--primary), var(--secondary));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        .mt-4 { margin-top: 16px; }
        .mt-6 { margin-top: 24px; }
        .mt-8 { margin-top: 32px; }
        .mt-12 { margin-top: 48px; }
        .mb-4 { margin-bottom: 16px; }
        .mb-6 { margin-bottom: 24px; }
        .mb-8 { margin-bottom: 32px; }
        .mx-auto { margin-left: auto; margin-right: auto; }

        /* ===== Button ===== */
        .btn {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            padding: 10px 24px;
            font-size: 0.95rem;
            font-weight: 600;
            border-radius: var(--radius-sm);
            transition: var(--transition);
            border: 2px solid transparent;
            white-space: nowrap;
        }
        .btn-primary {
            background: linear-gradient(135deg, var(--primary), var(--primary-light));
            color: #fff;
            box-shadow: 0 4px 14px rgba(79, 70, 229, 0.3);
        }
        .btn-primary:hover {
            transform: translateY(-2px);
            box-shadow: 0 8px 28px rgba(79, 70, 229, 0.4);
        }
        .btn-primary:active { transform: translateY(0); }
        .btn-outline {
            background: transparent;
            color: var(--primary);
            border-color: var(--primary);
        }
        .btn-outline:hover {
            background: var(--primary);
            color: #fff;
            transform: translateY(-2px);
        }
        .btn-outline:active { transform: translateY(0); }
        .btn-sm { padding: 6px 16px; font-size: 0.85rem; border-radius: var(--radius-xs); }
        .btn-lg { padding: 14px 36px; font-size: 1.05rem; }

        /* ===== Tag / Badge ===== */
        .tag {
            display: inline-block;
            padding: 4px 14px;
            font-size: 0.8rem;
            font-weight: 500;
            border-radius: 20px;
            background: var(--primary-bg);
            color: var(--primary);
            transition: var(--transition);
        }
        .tag:hover { background: var(--primary); color: #fff; }
        .tag-accent { background: #fef3c7; color: #d97706; }
        .tag-accent:hover { background: #f59e0b; color: #fff; }
        .tag-green { background: #d1fae5; color: #059669; }
        .tag-green:hover { background: #10b981; color: #fff; }

        /* ===== Header & Navigation ===== */
        .site-header {
            position: sticky;
            top: 0;
            z-index: 100;
            background: rgba(255,255,255,0.92);
            backdrop-filter: blur(16px);
            -webkit-backdrop-filter: blur(16px);
            border-bottom: 1px solid var(--border-light);
            height: var(--nav-height);
            display: flex;
            align-items: center;
        }
        .header-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            width: 100%;
        }
        .logo {
            font-size: 1.6rem;
            font-weight: 800;
            letter-spacing: -0.02em;
            background: linear-gradient(135deg, var(--primary), var(--secondary));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            flex-shrink: 0;
        }
        .logo-icon {
            width: 36px;
            height: 36px;
            background: linear-gradient(135deg, var(--primary), var(--secondary));
            border-radius: var(--radius-xs);
            display: flex;
            align-items: center;
            justify-content: center;
            color: #fff;
            font-size: 1.1rem;
            font-weight: 800;
            flex-shrink: 0;
        }
        .nav-links { display: flex; align-items: center; gap: 32px; }
        .nav-link {
            font-size: 0.95rem;
            font-weight: 500;
            color: var(--text-secondary);
            padding: 6px 0;
            position: relative;
            transition: var(--transition);
        }
        .nav-link::after {
            content: '';
            position: absolute;
            bottom: -2px;
            left: 0;
            width: 0;
            height: 2px;
            background: linear-gradient(90deg, var(--primary), var(--secondary));
            transition: var(--transition);
            border-radius: 2px;
        }
        .nav-link:hover { color: var(--primary); }
        .nav-link:hover::after { width: 100%; }
        .nav-link.active { color: var(--primary); font-weight: 600; }
        .nav-link.active::after { width: 100%; }
        .nav-cta {
            background: linear-gradient(135deg, var(--primary), var(--primary-light));
            color: #fff !important;
            padding: 8px 20px !important;
            border-radius: var(--radius-sm);
            font-weight: 600;
            box-shadow: 0 4px 14px rgba(79,70,229,0.25);
        }
        .nav-cta:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(79,70,229,0.35); }
        .nav-cta::after { display: none !important; }

        .header-right { display: flex; align-items: center; gap: 16px; }
        .search-box {
            display: flex;
            align-items: center;
            background: var(--bg-alt);
            border: 1px solid var(--border);
            border-radius: 24px;
            padding: 0 16px;
            height: 40px;
            transition: var(--transition);
        }
        .search-box:focus-within { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(79,70,229,0.1); }
        .search-box input {
            border: none;
            background: transparent;
            padding: 8px 0;
            font-size: 0.9rem;
            color: var(--text);
            outline: none;
            width: 140px;
        }
        .search-box input::placeholder { color: var(--text-muted); }
        .search-box i { color: var(--text-muted); font-size: 0.95rem; }

        .hamburger {
            display: none;
            flex-direction: column;
            gap: 5px;
            padding: 8px;
            cursor: pointer;
            background: none;
            border: none;
        }
        .hamburger span {
            display: block;
            width: 24px;
            height: 2px;
            background: var(--text);
            border-radius: 2px;
            transition: var(--transition);
        }

        /* ===== Article Hero ===== */
        .article-hero {
            background: linear-gradient(135deg, #eef2ff 0%, #f0fdf4 100%);
            padding: 60px 0 40px;
            position: relative;
            overflow: hidden;
        }
        .article-hero::before {
            content: '';
            position: absolute;
            top: -40%;
            right: -10%;
            width: 400px;
            height: 400px;
            background: radial-gradient(circle, rgba(79,70,229,0.06) 0%, transparent 70%);
            border-radius: 50%;
        }
        .article-hero .container { position: relative; z-index: 1; }
        .article-breadcrumb {
            display: flex;
            align-items: center;
            gap: 8px;
            font-size: 0.85rem;
            color: var(--text-muted);
            margin-bottom: 20px;
            flex-wrap: wrap;
        }
        .article-breadcrumb a { color: var(--text-secondary); }
        .article-breadcrumb a:hover { color: var(--primary); }
        .article-breadcrumb .sep { color: var(--text-muted); }
        .article-hero-title {
            font-size: 2.4rem;
            font-weight: 800;
            line-height: 1.25;
            color: var(--text);
            max-width: 800px;
            margin-bottom: 16px;
        }
        .article-meta {
            display: flex;
            align-items: center;
            gap: 20px;
            font-size: 0.9rem;
            color: var(--text-secondary);
            flex-wrap: wrap;
        }
        .article-meta .meta-item {
            display: flex;
            align-items: center;
            gap: 6px;
        }
        .article-meta i { color: var(--text-muted); font-size: 0.85rem; }
        .article-meta .tag { font-size: 0.75rem; padding: 2px 12px; }

        /* ===== Article Content ===== */
        .article-main {
            padding: 48px 0 64px;
        }
        .article-layout {
            display: grid;
            grid-template-columns: 1fr 300px;
            gap: 48px;
        }
        .article-body {
            background: var(--bg-card);
            border-radius: var(--radius);
            padding: 40px 44px;
            box-shadow: var(--shadow-card);
            border: 1px solid var(--border-light);
        }
        .article-body .content {
            font-size: 1.05rem;
            line-height: 1.85;
            color: var(--text);
        }
        .article-body .content p {
            margin-bottom: 1.4em;
        }
        .article-body .content h2 {
            font-size: 1.6rem;
            margin-top: 2em;
            margin-bottom: 0.8em;
            color: var(--text);
        }
        .article-body .content h3 {
            font-size: 1.25rem;
            margin-top: 1.6em;
            margin-bottom: 0.6em;
            color: var(--text);
        }
        .article-body .content ul,
        .article-body .content ol {
            margin-bottom: 1.4em;
            padding-left: 1.6em;
        }
        .article-body .content li {
            margin-bottom: 0.4em;
            list-style: disc;
        }
        .article-body .content ol li { list-style: decimal; }
        .article-body .content blockquote {
            border-left: 4px solid var(--primary);
            background: var(--primary-bg);
            padding: 16px 24px;
            margin: 1.6em 0;
            border-radius: 0 var(--radius-xs) var(--radius-xs) 0;
            color: var(--text-secondary);
            font-style: italic;
        }
        .article-body .content img {
            border-radius: var(--radius-sm);
            margin: 1.6em 0;
            box-shadow: var(--shadow);
        }
        .article-body .content a {
            color: var(--primary);
            text-decoration: underline;
            text-underline-offset: 2px;
        }
        .article-body .content a:hover { color: var(--primary-dark); }

        .article-footer-meta {
            margin-top: 40px;
            padding-top: 24px;
            border-top: 1px solid var(--border);
            display: flex;
            align-items: center;
            justify-content: space-between;
            flex-wrap: wrap;
            gap: 16px;
        }
        .article-tags {
            display: flex;
            align-items: center;
            gap: 8px;
            flex-wrap: wrap;
        }
        .article-tags .tag { font-size: 0.8rem; }
        .article-share {
            display: flex;
            align-items: center;
            gap: 10px;
        }
        .article-share a {
            width: 36px;
            height: 36px;
            display: flex;
            align-items: center;
            justify-content: center;
            border-radius: 50%;
            background: var(--bg-alt);
            color: var(--text-secondary);
            border: 1px solid var(--border);
            transition: var(--transition);
        }
        .article-share a:hover {
            background: var(--primary);
            color: #fff;
            border-color: var(--primary);
            transform: translateY(-2px);
        }

        /* ===== Sidebar ===== */
        .article-sidebar {
            display: flex;
            flex-direction: column;
            gap: 32px;
        }
        .sidebar-card {
            background: var(--bg-card);
            border-radius: var(--radius);
            padding: 28px;
            box-shadow: var(--shadow-card);
            border: 1px solid var(--border-light);
        }
        .sidebar-card h3 {
            font-size: 1.1rem;
            font-weight: 700;
            margin-bottom: 16px;
            padding-bottom: 12px;
            border-bottom: 2px solid var(--primary-bg);
            color: var(--text);
        }
        .sidebar-list { display: flex; flex-direction: column; gap: 12px; }
        .sidebar-list-item {
            display: flex;
            align-items: flex-start;
            gap: 12px;
            padding: 10px 0;
            border-bottom: 1px solid var(--border-light);
            transition: var(--transition);
        }
        .sidebar-list-item:last-child { border-bottom: none; }
        .sidebar-list-item:hover { padding-left: 4px; }
        .sidebar-list-item .num {
            width: 26px;
            height: 26px;
            border-radius: var(--radius-xs);
            background: var(--primary-bg);
            color: var(--primary);
            font-size: 0.75rem;
            font-weight: 700;
            display: flex;
            align-items: center;
            justify-content: center;
            flex-shrink: 0;
        }
        .sidebar-list-item .num.top { background: var(--primary); color: #fff; }
        .sidebar-list-item .item-text { font-size: 0.9rem; color: var(--text-secondary); line-height: 1.4; }
        .sidebar-list-item .item-text:hover { color: var(--primary); }

        .sidebar-cta {
            background: linear-gradient(135deg, var(--primary), var(--primary-dark));
            color: #fff;
            border-radius: var(--radius);
            padding: 32px 28px;
            text-align: center;
        }
        .sidebar-cta h4 { font-size: 1.15rem; font-weight: 700; color: #fff; margin-bottom: 8px; }
        .sidebar-cta p { font-size: 0.9rem; opacity: 0.85; margin-bottom: 20px; }
        .sidebar-cta .btn {
            background: #fff;
            color: var(--primary);
            font-weight: 700;
        }
        .sidebar-cta .btn:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(0,0,0,0.2); }

        /* ===== Related Section ===== */
        .related-section {
            background: var(--bg-alt);
            padding: 60px 0;
        }
        .related-section .section-title {
            font-size: 1.8rem;
            font-weight: 800;
            text-align: center;
            margin-bottom: 40px;
        }
        .related-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 24px;
        }
        .related-card {
            background: var(--bg-card);
            border-radius: var(--radius);
            overflow: hidden;
            box-shadow: var(--shadow-card);
            border: 1px solid var(--border-light);
            transition: var(--transition);
        }
        .related-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); }
        .related-card-img {
            height: 180px;
            background: linear-gradient(135deg, var(--primary-bg), #f0fdf4);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 2.4rem;
            color: var(--primary-light);
        }
        .related-card-body { padding: 20px 24px 24px; }
        .related-card-body h4 {
            font-size: 1.05rem;
            font-weight: 700;
            margin-bottom: 8px;
            display: -webkit-box;
            -webkit-line-clamp: 2;
            -webkit-box-orient: vertical;
            overflow: hidden;
        }
        .related-card-body h4 a:hover { color: var(--primary); }
        .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;
            margin-bottom: 12px;
        }
        .related-card-body .meta { font-size: 0.8rem; color: var(--text-muted); display: flex; align-items: center; gap: 12px; }

        /* ===== Not Found ===== */
        .not-found-page {
            min-height: 60vh;
            display: flex;
            align-items: center;
            justify-content: center;
            text-align: center;
            padding: 80px 24px;
        }
        .not-found-page .nf-icon {
            font-size: 4rem;
            color: var(--text-muted);
            margin-bottom: 24px;
        }
        .not-found-page h1 { font-size: 2rem; margin-bottom: 12px; }
        .not-found-page p { color: var(--text-secondary); margin-bottom: 24px; max-width: 480px; margin-left: auto; margin-right: auto; }

        /* ===== Footer ===== */
        .site-footer {
            background: #0f172a;
            color: #cbd5e1;
            padding: 60px 0 0;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr 1fr;
            gap: 40px;
            padding-bottom: 40px;
            border-bottom: 1px solid rgba(255,255,255,0.08);
        }
        .footer-brand .logo { font-size: 1.5rem; }
        .footer-brand p { font-size: 0.9rem; color: #94a3b8; margin-top: 12px; max-width: 320px; line-height: 1.7; }
        .footer-col h4 {
            color: #fff;
            font-size: 1rem;
            font-weight: 600;
            margin-bottom: 16px;
        }
        .footer-col a {
            display: block;
            font-size: 0.88rem;
            color: #94a3b8;
            padding: 4px 0;
            transition: var(--transition);
        }
        .footer-col a:hover { color: var(--secondary-light); padding-left: 4px; }
        .footer-bottom {
            padding: 24px 0;
            text-align: center;
            font-size: 0.85rem;
            color: #64748b;
        }
        .footer-bottom a { color: #94a3b8; }
        .footer-bottom a:hover { color: #fff; }

        /* ===== Responsive ===== */
        @media (max-width: 1024px) {
            .article-layout { grid-template-columns: 1fr; }
            .article-sidebar { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
            .related-grid { grid-template-columns: 1fr 1fr; }
            .footer-grid { grid-template-columns: 1fr 1fr; }
        }

        @media (max-width: 768px) {
            :root { --nav-height: 64px; }
            .container { padding: 0 16px; }
            .nav-links {
                position: fixed;
                top: var(--nav-height);
                left: 0;
                right: 0;
                background: rgba(255,255,255,0.98);
                backdrop-filter: blur(16px);
                flex-direction: column;
                padding: 24px 32px;
                gap: 16px;
                border-bottom: 1px solid var(--border);
                transform: translateY(-120%);
                opacity: 0;
                transition: var(--transition);
                box-shadow: 0 16px 40px rgba(0,0,0,0.08);
                z-index: 99;
            }
            .nav-links.open { transform: translateY(0); opacity: 1; }
            .nav-link { font-size: 1.05rem; }
            .hamburger { display: flex; }
            .search-box input { width: 100px; }
            .article-hero { padding: 40px 0 28px; }
            .article-hero-title { font-size: 1.6rem; }
            .article-body { padding: 24px 20px; }
            .article-body .content { font-size: 0.98rem; }
            .article-layout { grid-template-columns: 1fr; }
            .article-sidebar { grid-template-columns: 1fr; }
            .related-grid { grid-template-columns: 1fr; }
            .footer-grid { grid-template-columns: 1fr; gap: 32px; }
            .article-meta { gap: 12px; font-size: 0.82rem; }
            .article-footer-meta { flex-direction: column; align-items: flex-start; }
            .sidebar-card { padding: 20px; }
        }

        @media (max-width: 520px) {
            .article-hero-title { font-size: 1.35rem; }
            .header-right .search-box { display: none; }
            .nav-cta { padding: 6px 14px !important; font-size: 0.85rem; }
            .article-body { padding: 16px 14px; }
            .article-body .content { font-size: 0.95rem; }
            .article-body .content h2 { font-size: 1.3rem; }
            .article-body .content h3 { font-size: 1.1rem; }
            .related-card-img { height: 140px; }
            .not-found-page h1 { font-size: 1.5rem; }
        }

        /* ===== Focus / Accessibility ===== */
        a:focus-visible, button:focus-visible, input:focus-visible {
            outline: 2px solid var(--primary);
            outline-offset: 2px;
            border-radius: var(--radius-xs);
        }

/* roulang page: category1 */
/* ===== CSS Design Variables ===== */
        :root {
            --primary: #4f46e5;
            --primary-light: #6366f1;
            --primary-dark: #3730a3;
            --primary-bg: #eef2ff;
            --secondary: #06b6d4;
            --secondary-light: #22d3ee;
            --accent: #f59e0b;
            --accent-light: #fbbf24;
            --bg: #ffffff;
            --bg-alt: #f8fafc;
            --bg-dark: #0f172a;
            --text: #1e293b;
            --text-light: #64748b;
            --text-muted: #94a3b8;
            --text-inverse: #f1f5f9;
            --border: #e2e8f0;
            --border-light: #f1f5f9;
            --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 16px rgba(0, 0, 0, 0.08), 0 2px 8px rgba(0, 0, 0, 0.04);
            --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.12), 0 4px 16px rgba(0, 0, 0, 0.06);
            --shadow-xl: 0 24px 60px rgba(0, 0, 0, 0.15);
            --font-sans: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
            --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
            --max-width: 1280px;
            --header-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-sans);
            font-size: 16px;
            line-height: 1.7;
            color: var(--text);
            background: var(--bg);
            padding-top: var(--header-height);
        }
        img { max-width: 100%; height: auto; display: block; }
        a { color: inherit; text-decoration: none; transition: color var(--transition); }
        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; font-weight: 700; color: var(--text); }
        h1 { font-size: clamp(2rem, 5vw, 3.2rem); letter-spacing: -0.02em; }
        h2 { font-size: clamp(1.5rem, 3.5vw, 2.2rem); letter-spacing: -0.01em; }
        h3 { font-size: clamp(1.15rem, 2vw, 1.4rem); }
        h4 { font-size: 1.1rem; }
        p { margin-bottom: 1rem; color: var(--text-light); }
        .container {
            max-width: var(--max-width);
            margin: 0 auto;
            padding: 0 24px;
        }
        .section { padding: 80px 0; }
        .section-alt { background: var(--bg-alt); }
        .section-dark { background: var(--bg-dark); color: var(--text-inverse); }
        .section-dark h2,
        .section-dark h3,
        .section-dark h4 { color: #ffffff; }
        .section-dark p { color: #cbd5e1; }
        .gradient-text {
            background: linear-gradient(135deg, var(--primary), var(--secondary));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }

        /* ===== Buttons ===== */
        .btn {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 12px 28px;
            border-radius: var(--radius-md);
            font-weight: 600;
            font-size: 0.95rem;
            transition: all var(--transition);
            border: 2px solid transparent;
            white-space: nowrap;
        }
        .btn-primary {
            background: var(--primary);
            color: #ffffff;
            box-shadow: 0 4px 14px rgba(79, 70, 229, 0.35);
        }
        .btn-primary:hover {
            background: var(--primary-dark);
            transform: translateY(-2px);
            box-shadow: 0 8px 24px rgba(79, 70, 229, 0.4);
        }
        .btn-primary:active { transform: translateY(0); }
        .btn-secondary {
            background: transparent;
            color: var(--primary);
            border-color: var(--primary);
        }
        .btn-secondary:hover {
            background: var(--primary);
            color: #ffffff;
            transform: translateY(-2px);
        }
        .btn-accent {
            background: var(--accent);
            color: #1e293b;
            box-shadow: 0 4px 14px rgba(245, 158, 11, 0.35);
        }
        .btn-accent:hover {
            background: var(--accent-light);
            transform: translateY(-2px);
            box-shadow: 0 8px 24px rgba(245, 158, 11, 0.4);
        }
        .btn-lg { padding: 16px 36px; font-size: 1.05rem; }
        .btn-sm { padding: 8px 18px; font-size: 0.85rem; }
        .btn:focus-visible { outline: 3px solid var(--primary-light); outline-offset: 2px; }

        /* ===== Tags / Badges ===== */
        .tag {
            display: inline-block;
            padding: 4px 14px;
            border-radius: 50px;
            font-size: 0.78rem;
            font-weight: 600;
            background: var(--primary-bg);
            color: var(--primary);
            border: 1px solid rgba(79, 70, 229, 0.15);
        }
        .tag-accent { background: #fef3c7; color: #d97706; border-color: rgba(245, 158, 11, 0.2); }
        .tag-green { background: #ecfdf5; color: #059669; border-color: rgba(5, 150, 105, 0.15); }
        .tag-blue { background: #eff6ff; color: #2563eb; border-color: rgba(37, 99, 235, 0.15); }
        .tag-purple { background: #f5f3ff; color: #7c3aed; border-color: rgba(124, 58, 237, 0.15); }

        /* ===== Header / Nav ===== */
        .site-header {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            z-index: 1000;
            height: var(--header-height);
            background: rgba(255, 255, 255, 0.95);
            backdrop-filter: blur(16px);
            -webkit-backdrop-filter: blur(16px);
            border-bottom: 1px solid var(--border);
            box-shadow: 0 1px 8px rgba(0, 0, 0, 0.04);
        }
        .site-header .container {
            display: flex;
            align-items: center;
            justify-content: space-between;
            height: 100%;
        }
        .logo {
            font-size: 1.5rem;
            font-weight: 800;
            letter-spacing: -0.03em;
            background: linear-gradient(135deg, var(--primary), var(--secondary));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            white-space: nowrap;
        }
        .logo-icon {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            width: 36px;
            height: 36px;
            background: linear-gradient(135deg, var(--primary), var(--secondary));
            border-radius: var(--radius-sm);
            color: #fff;
            font-size: 1.1rem;
            margin-right: 10px;
        }
        .nav-links { display: flex; align-items: center; gap: 32px; }
        .nav-link {
            font-size: 0.92rem;
            font-weight: 500;
            color: var(--text-light);
            position: relative;
            padding: 4px 0;
            transition: color var(--transition);
        }
        .nav-link::after {
            content: '';
            position: absolute;
            bottom: -4px;
            left: 0;
            width: 0;
            height: 2.5px;
            background: var(--primary);
            border-radius: 4px;
            transition: width var(--transition);
        }
        .nav-link:hover { color: var(--text); }
        .nav-link:hover::after { width: 100%; }
        .nav-link.active { color: var(--primary); }
        .nav-link.active::after { width: 100%; }
        .nav-cta .btn { padding: 10px 22px; font-size: 0.88rem; }
        .nav-search {
            display: flex;
            align-items: center;
            background: var(--bg-alt);
            border-radius: 50px;
            padding: 0 16px;
            border: 1px solid var(--border);
            transition: all var(--transition);
        }
        .nav-search:focus-within { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1); }
        .nav-search input {
            border: none;
            background: transparent;
            padding: 8px 10px;
            font-size: 0.88rem;
            color: var(--text);
            outline: none;
            width: 160px;
        }
        .nav-search input::placeholder { color: var(--text-muted); }
        .nav-search i { color: var(--text-muted); font-size: 0.9rem; }
        .mobile-toggle { display: none; font-size: 1.5rem; color: var(--text); padding: 4px; }

        /* ===== Hero ===== */
        .hero-category {
            padding: 100px 0 80px;
            background: linear-gradient(135deg, var(--primary-bg) 0%, #f0f4ff 50%, #eef2ff 100%);
            position: relative;
            overflow: hidden;
        }
        .hero-category::before {
            content: '';
            position: absolute;
            top: -40%;
            right: -20%;
            width: 500px;
            height: 500px;
            background: radial-gradient(circle, rgba(79, 70, 229, 0.08) 0%, transparent 70%);
            border-radius: 50%;
            pointer-events: none;
        }
        .hero-category::after {
            content: '';
            position: absolute;
            bottom: -30%;
            left: -15%;
            width: 400px;
            height: 400px;
            background: radial-gradient(circle, rgba(6, 182, 212, 0.06) 0%, transparent 70%);
            border-radius: 50%;
            pointer-events: none;
        }
        .hero-category .container { position: relative; z-index: 1; }
        .hero-category h1 { margin-bottom: 16px; }
        .hero-category p { font-size: 1.15rem; max-width: 640px; margin-bottom: 28px; }
        .hero-stats {
            display: flex;
            gap: 40px;
            margin-top: 40px;
            padding-top: 32px;
            border-top: 1px solid var(--border);
        }
        .hero-stat strong { display: block; font-size: 1.8rem; color: var(--primary); }
        .hero-stat span { font-size: 0.88rem; color: var(--text-muted); }

        /* ===== Cards ===== */
        .card {
            background: var(--bg);
            border-radius: var(--radius-md);
            box-shadow: var(--shadow-sm);
            border: 1px solid var(--border);
            overflow: hidden;
            transition: all var(--transition);
        }
        .card:hover {
            box-shadow: var(--shadow-lg);
            transform: translateY(-4px);
            border-color: rgba(79, 70, 229, 0.1);
        }
        .card-img { width: 100%; aspect-ratio: 16/10; object-fit: cover; }
        .card-body { padding: 24px; }
        .card-body h3 { margin-bottom: 8px; }
        .card-body p { font-size: 0.92rem; margin-bottom: 16px; }
        .card-meta { display: flex; align-items: center; gap: 16px; font-size: 0.82rem; color: var(--text-muted); }

        /* ===== Grid ===== */
        .grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; }
        .grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 28px; }
        .grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }

        /* ===== Category Tabs ===== */
        .category-tabs {
            display: flex;
            flex-wrap: wrap;
            gap: 12px;
            margin-bottom: 40px;
        }
        .category-tab {
            padding: 10px 24px;
            border-radius: 50px;
            font-size: 0.9rem;
            font-weight: 500;
            background: var(--bg);
            border: 1px solid var(--border);
            color: var(--text-light);
            transition: all var(--transition);
            cursor: pointer;
        }
        .category-tab:hover { border-color: var(--primary); color: var(--primary); background: var(--primary-bg); }
        .category-tab.active { background: var(--primary); color: #fff; border-color: var(--primary); }

        /* ===== Guide Flow ===== */
        .guide-flow { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
        .flow-step {
            text-align: center;
            padding: 32px 20px;
            background: var(--bg);
            border-radius: var(--radius-md);
            border: 1px solid var(--border);
            transition: all var(--transition);
            position: relative;
        }
        .flow-step:hover { box-shadow: var(--shadow-md); transform: translateY(-2px); }
        .flow-step .step-num {
            width: 48px;
            height: 48px;
            border-radius: 50%;
            background: var(--primary-bg);
            color: var(--primary);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.2rem;
            font-weight: 700;
            margin: 0 auto 16px;
        }
        .flow-step h4 { margin-bottom: 8px; }
        .flow-step p { font-size: 0.88rem; margin-bottom: 0; }
        .flow-arrow {
            display: flex;
            align-items: center;
            justify-content: center;
            color: var(--text-muted);
            font-size: 1.4rem;
        }

        /* ===== FAQ ===== */
        .faq-list { max-width: 800px; margin: 0 auto; }
        .faq-item {
            border-bottom: 1px solid var(--border);
            padding: 20px 0;
        }
        .faq-item:first-child { padding-top: 0; }
        .faq-question {
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-weight: 600;
            font-size: 1.05rem;
            cursor: pointer;
            color: var(--text);
            background: none;
            width: 100%;
            text-align: left;
            padding: 4px 0;
        }
        .faq-question i { color: var(--text-muted); transition: transform var(--transition); font-size: 0.9rem; }
        .faq-question[aria-expanded="true"] i { transform: rotate(180deg); }
        .faq-answer {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.35s ease, padding 0.35s ease;
            padding: 0 0;
        }
        .faq-answer.open { max-height: 300px; padding: 12px 0 4px; }
        .faq-answer p { font-size: 0.95rem; margin-bottom: 0; }

        /* ===== CTA ===== */
        .cta-block {
            background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
            border-radius: var(--radius-lg);
            padding: 64px 48px;
            text-align: center;
            color: #ffffff;
        }
        .cta-block h2 { color: #ffffff; margin-bottom: 12px; }
        .cta-block p { color: #c7d2fe; margin-bottom: 28px; max-width: 600px; margin-left: auto; margin-right: auto; }
        .cta-block .btn { background: #ffffff; color: var(--primary); }
        .cta-block .btn:hover { background: var(--bg-alt); transform: translateY(-2px); }

        /* ===== Footer ===== */
        .site-footer {
            background: var(--bg-dark);
            color: var(--text-inverse);
            padding: 60px 0 0;
        }
        .site-footer .container { max-width: var(--max-width); }
        .footer-grid {
            display: grid;
            grid-template-columns: 1.8fr 1fr 1fr 1fr;
            gap: 48px;
            padding-bottom: 40px;
            border-bottom: 1px solid rgba(255, 255, 255, 0.08);
        }
        .footer-brand .logo { font-size: 1.4rem; }
        .footer-brand p { color: #94a3b8; font-size: 0.92rem; margin: 12px 0 0; }
        .footer-col h4 { color: #ffffff; font-size: 0.95rem; margin-bottom: 18px; font-weight: 600; }
        .footer-col a {
            display: block;
            color: #94a3b8;
            font-size: 0.88rem;
            padding: 5px 0;
            transition: color var(--transition);
        }
        .footer-col a:hover { color: #ffffff; }
        .footer-bottom {
            padding: 24px 0;
            text-align: center;
            color: #64748b;
            font-size: 0.85rem;
        }
        .footer-bottom p { margin-bottom: 0; color: #64748b; }

        /* ===== Responsive ===== */
        @media (max-width: 1024px) {
            .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
            .guide-flow { grid-template-columns: repeat(2, 1fr); }
            .flow-arrow { display: none; }
        }

        @media (max-width: 768px) {
            :root { --header-height: 64px; }
            .nav-links { display: none; }
            .nav-search { display: none; }
            .nav-cta .btn { padding: 8px 16px; font-size: 0.82rem; }
            .mobile-toggle { display: block; }
            .nav-links.mobile-open {
                display: flex;
                flex-direction: column;
                position: absolute;
                top: var(--header-height);
                left: 0;
                right: 0;
                background: rgba(255, 255, 255, 0.98);
                backdrop-filter: blur(16px);
                padding: 20px 24px;
                gap: 16px;
                border-bottom: 1px solid var(--border);
                box-shadow: var(--shadow-md);
            }
            .nav-links.mobile-open .nav-link { font-size: 1rem; padding: 8px 0; }
            .nav-links.mobile-open .nav-cta { margin-top: 8px; }

            .hero-category { padding: 80px 0 60px; }
            .hero-stats { gap: 24px; flex-wrap: wrap; }
            .hero-stat strong { font-size: 1.4rem; }

            .grid-3, .grid-4 { grid-template-columns: 1fr; }
            .grid-2 { grid-template-columns: 1fr; }
            .guide-flow { grid-template-columns: 1fr; }

            .footer-grid { grid-template-columns: 1fr; gap: 24px; }

            .cta-block { padding: 40px 24px; }
            .section { padding: 56px 0; }
            .category-tabs { gap: 8px; }
            .category-tab { padding: 8px 16px; font-size: 0.82rem; }
        }

        @media (max-width: 520px) {
            .container { padding: 0 16px; }
            .hero-category h1 { font-size: 1.8rem; }
            .hero-category p { font-size: 0.95rem; }
            .hero-stats { flex-direction: column; gap: 12px; }
            .btn-lg { padding: 14px 28px; font-size: 0.95rem; }
            .card-body { padding: 18px; }
        }

        /* ===== Animations ===== */
        @keyframes fadeUp {
            from { opacity: 0; transform: translateY(24px); }
            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; }

        /* ===== Misc Utilities ===== */
        .text-center { text-align: center; }
        .flex { display: flex; }
        .flex-wrap { flex-wrap: wrap; }
        .items-center { align-items: center; }
        .justify-center { justify-content: center; }
        .gap-2 { gap: 8px; }
        .gap-4 { gap: 16px; }
        .gap-6 { gap: 24px; }
        .gap-8 { gap: 32px; }
        .mt-2 { margin-top: 8px; }
        .mt-4 { margin-top: 16px; }
        .mt-6 { margin-top: 24px; }
        .mt-8 { margin-top: 32px; }
        .mb-4 { margin-bottom: 16px; }
        .mb-6 { margin-bottom: 24px; }
        .mb-8 { margin-bottom: 32px; }
        .mx-auto { margin-left: auto; margin-right: auto; }
        .text-muted { color: var(--text-muted); }
        .text-sm { font-size: 0.88rem; }
        .text-xs { font-size: 0.78rem; }
        .font-bold { font-weight: 700; }
        .max-w-2xl { max-width: 640px; }
        .max-w-3xl { max-width: 768px; }
        .w-full { width: 100%; }
        .hidden { display: none; }
        .inline-flex { display: inline-flex; }