/* roulang page: index */
/* ===== Design Variables ===== */
        :root {
            --primary: #1a3a6b;
            --primary-light: #2a5a9e;
            --primary-dark: #0f2444;
            --secondary: #f59e0b;
            --secondary-light: #fbbf24;
            --accent: #06b6d4;
            --bg-white: #ffffff;
            --bg-light: #f8fafc;
            --bg-dark: #0f172a;
            --text-dark: #1e293b;
            --text-mid: #475569;
            --text-light: #94a3b8;
            --text-white: #f1f5f9;
            --border: #e2e8f0;
            --border-light: #f1f5f9;
            --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
            --shadow-md: 0 4px 16px rgba(0,0,0,0.08);
            --shadow-lg: 0 12px 40px rgba(0,0,0,0.12);
            --radius-sm: 8px;
            --radius-md: 16px;
            --radius-lg: 24px;
            --radius-xl: 32px;
            --sp-xs: 8px;
            --sp-sm: 16px;
            --sp-md: 32px;
            --sp-lg: 64px;
            --sp-xl: 96px;
            --font-sans: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
            --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
        }

        /* ===== Reset & Base ===== */
        *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
        html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
        body {
            font-family: var(--font-sans);
            font-size: 16px;
            line-height: 1.7;
            color: var(--text-dark);
            background: var(--bg-white);
            -webkit-font-smoothing: antialiased;
        }
        img { max-width: 100%; height: auto; display: block; }
        a { color: var(--primary-light); text-decoration: none; transition: var(--transition); }
        a:hover { color: var(--primary); }
        button, input, textarea { font-family: inherit; font-size: inherit; }
        button { cursor: pointer; border: none; background: none; }
        ul, ol { list-style: none; }
        h1, h2, h3, h4, h5, h6 { line-height: 1.3; color: var(--text-dark); font-weight: 700; }

        /* ===== Container ===== */
        .container { max-width: 1200px; margin: 0 auto; padding: 0 var(--sp-sm); }
        .container-narrow { max-width: 800px; margin: 0 auto; padding: 0 var(--sp-sm); }

        /* ===== Section Spacing ===== */
        .section { padding: var(--sp-lg) 0; }
        .section-title {
            text-align: center;
            margin-bottom: var(--sp-md);
            font-size: 2rem;
            font-weight: 800;
            letter-spacing: -0.02em;
        }
        .section-subtitle {
            text-align: center;
            max-width: 640px;
            margin: -0.5rem auto var(--sp-md);
            color: var(--text-mid);
            font-size: 1.1rem;
        }
        .section-divider {
            width: 60px;
            height: 4px;
            background: var(--secondary);
            border-radius: 4px;
            margin: var(--sp-sm) auto var(--sp-md);
        }

        /* ===== Header & Navigation ===== */
        .site-header {
            background: var(--bg-white);
            border-bottom: 1px solid var(--border);
            position: sticky;
            top: 0;
            z-index: 100;
            box-shadow: var(--shadow-sm);
        }
        .header-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 0 var(--sp-sm);
            height: 68px;
            max-width: 1200px;
            margin: 0 auto;
        }
        .logo {
            font-size: 1.35rem;
            font-weight: 800;
            color: var(--primary);
            letter-spacing: -0.03em;
            display: flex;
            align-items: center;
            gap: 8px;
        }
        .logo i { color: var(--secondary); font-size: 1.5rem; }
        .logo span { background: linear-gradient(135deg, var(--primary), var(--primary-light)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
        .logo:hover { opacity: 0.9; }

        .nav-list {
            display: flex;
            align-items: center;
            gap: 4px;
        }
        .nav-list a {
            padding: 8px 18px;
            border-radius: var(--radius-sm);
            color: var(--text-mid);
            font-weight: 500;
            font-size: 0.95rem;
            transition: var(--transition);
            position: relative;
        }
        .nav-list a:hover { color: var(--primary); background: var(--bg-light); }
        .nav-list a.active {
            color: var(--primary);
            background: rgba(26,58,107,0.08);
            font-weight: 600;
        }
        .nav-list a.active::after {
            content: '';
            position: absolute;
            bottom: 2px;
            left: 50%;
            transform: translateX(-50%);
            width: 20px;
            height: 3px;
            background: var(--secondary);
            border-radius: 4px;
        }
        .nav-cta {
            background: var(--primary) !important;
            color: #fff !important;
            padding: 10px 24px !important;
            border-radius: var(--radius-sm) !important;
            font-weight: 600 !important;
            box-shadow: 0 4px 12px rgba(26,58,107,0.25);
        }
        .nav-cta:hover { background: var(--primary-light) !important; transform: translateY(-1px); box-shadow: 0 6px 20px rgba(26,58,107,0.3) !important; }

        .nav-toggle { display: none; font-size: 1.5rem; color: var(--text-dark); padding: 4px 8px; border-radius: var(--radius-sm); }
        .nav-toggle:hover { background: var(--bg-light); }

        /* ===== Hero ===== */
        .hero {
            position: relative;
            min-height: 520px;
            display: flex;
            align-items: center;
            background: var(--bg-dark);
            overflow: hidden;
        }
        .hero-bg {
            position: absolute;
            inset: 0;
            background: url('/assets/images/backpic/back-1.png') center center / cover no-repeat;
            opacity: 0.35;
            transform: scale(1.05);
        }
        .hero-overlay {
            position: absolute;
            inset: 0;
            background: linear-gradient(135deg, rgba(15,36,68,0.92) 0%, rgba(26,58,107,0.7) 100%);
        }
        .hero-content {
            position: relative;
            z-index: 2;
            max-width: 720px;
            padding: var(--sp-lg) 0;
        }
        .hero-badge {
            display: inline-flex;
            align-items: center;
            gap: 6px;
            background: rgba(245,158,11,0.18);
            color: var(--secondary-light);
            font-size: 0.85rem;
            font-weight: 600;
            padding: 6px 16px;
            border-radius: 100px;
            border: 1px solid rgba(245,158,11,0.25);
            margin-bottom: var(--sp-sm);
        }
        .hero-title {
            font-size: 3rem;
            font-weight: 900;
            color: #fff;
            letter-spacing: -0.03em;
            line-height: 1.15;
            margin-bottom: var(--sp-sm);
        }
        .hero-title em { color: var(--secondary-light); font-style: normal; }
        .hero-desc {
            font-size: 1.15rem;
            color: rgba(255,255,255,0.8);
            max-width: 560px;
            line-height: 1.7;
            margin-bottom: var(--sp-md);
        }
        .hero-actions { display: flex; gap: var(--sp-sm); flex-wrap: wrap; }
        .btn {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 14px 32px;
            border-radius: var(--radius-sm);
            font-weight: 600;
            font-size: 1rem;
            transition: var(--transition);
            border: 2px solid transparent;
        }
        .btn-primary {
            background: var(--secondary);
            color: var(--primary-dark);
            border-color: var(--secondary);
            box-shadow: 0 4px 16px rgba(245,158,11,0.3);
        }
        .btn-primary:hover { background: var(--secondary-light); border-color: var(--secondary-light); transform: translateY(-2px); box-shadow: 0 8px 28px rgba(245,158,11,0.35); color: var(--primary-dark); }
        .btn-outline-light {
            background: transparent;
            color: #fff;
            border-color: rgba(255,255,255,0.3);
        }
        .btn-outline-light:hover { background: rgba(255,255,255,0.08); border-color: rgba(255,255,255,0.5); transform: translateY(-2px); color: #fff; }
        .hero-stats {
            display: flex;
            gap: var(--sp-md);
            margin-top: var(--sp-md);
            padding-top: var(--sp-md);
            border-top: 1px solid rgba(255,255,255,0.1);
        }
        .hero-stat { color: rgba(255,255,255,0.7); }
        .hero-stat strong { display: block; font-size: 1.8rem; font-weight: 800; color: #fff; }

        /* ===== Cards ===== */
        .card {
            background: var(--bg-white);
            border-radius: var(--radius-md);
            box-shadow: var(--shadow-sm);
            border: 1px solid var(--border);
            transition: var(--transition);
            overflow: hidden;
        }
        .card:hover { box-shadow: var(--shadow-md); transform: translateY(-4px); }
        .card-img { width: 100%; aspect-ratio: 16/9; object-fit: cover; }
        .card-body { padding: var(--sp-sm); }
        .card-tag {
            display: inline-block;
            font-size: 0.8rem;
            font-weight: 600;
            color: var(--primary);
            background: rgba(26,58,107,0.08);
            padding: 2px 12px;
            border-radius: 100px;
            margin-bottom: 6px;
        }
        .card-title { font-size: 1.15rem; font-weight: 700; margin-bottom: 6px; }
        .card-title a { color: var(--text-dark); }
        .card-title a:hover { color: var(--primary); }
        .card-desc { font-size: 0.92rem; color: var(--text-mid); line-height: 1.6; }
        .card-meta { display: flex; align-items: center; gap: var(--sp-sm); font-size: 0.85rem; color: var(--text-light); margin-top: 10px; }

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

        /* ===== Feature / Icon Blocks ===== */
        .feature-card {
            text-align: center;
            padding: var(--sp-md);
            border-radius: var(--radius-md);
            background: var(--bg-white);
            border: 1px solid var(--border);
            transition: var(--transition);
        }
        .feature-card:hover { box-shadow: var(--shadow-md); transform: translateY(-4px); }
        .feature-icon {
            width: 64px;
            height: 64px;
            border-radius: var(--radius-sm);
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0 auto var(--sp-sm);
            font-size: 1.8rem;
            color: #fff;
            background: var(--primary);
        }
        .feature-card h3 { font-size: 1.15rem; margin-bottom: 6px; }
        .feature-card p { font-size: 0.95rem; color: var(--text-mid); line-height: 1.6; }

        /* ===== Category Tabs ===== */
        .category-tabs {
            display: flex;
            flex-wrap: wrap;
            gap: 8px;
            justify-content: center;
            margin-bottom: var(--sp-md);
        }
        .category-tab {
            padding: 10px 24px;
            border-radius: 100px;
            background: var(--bg-light);
            color: var(--text-mid);
            font-weight: 500;
            font-size: 0.95rem;
            border: 1px solid var(--border);
            transition: var(--transition);
        }
        .category-tab:hover { background: var(--border); color: var(--text-dark); }
        .category-tab.active { background: var(--primary); color: #fff; border-color: var(--primary); box-shadow: 0 4px 12px rgba(26,58,107,0.2); }

        /* ===== Steps / Timeline ===== */
        .step-list { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: var(--sp-md); counter-reset: step; }
        .step-item {
            counter-increment: step;
            padding: var(--sp-md);
            background: var(--bg-white);
            border-radius: var(--radius-md);
            border: 1px solid var(--border);
            position: relative;
            transition: var(--transition);
        }
        .step-item:hover { box-shadow: var(--shadow-md); }
        .step-number {
            font-size: 2.5rem;
            font-weight: 900;
            color: rgba(26,58,107,0.08);
            line-height: 1;
            margin-bottom: 4px;
        }
        .step-item h3 { font-size: 1.1rem; margin-bottom: 6px; }
        .step-item p { font-size: 0.92rem; color: var(--text-mid); line-height: 1.6; }

        /* ===== FAQ ===== */
        .faq-list { max-width: 800px; margin: 0 auto; }
        .faq-item {
            border: 1px solid var(--border);
            border-radius: var(--radius-sm);
            margin-bottom: 10px;
            overflow: hidden;
            transition: var(--transition);
        }
        .faq-item:hover { border-color: var(--primary-light); }
        .faq-question {
            width: 100%;
            text-align: left;
            padding: 18px 20px;
            font-weight: 600;
            font-size: 1rem;
            color: var(--text-dark);
            background: var(--bg-light);
            display: flex;
            justify-content: space-between;
            align-items: center;
            transition: var(--transition);
        }
        .faq-question i { transition: var(--transition); color: var(--primary); }
        .faq-item.active .faq-question i { transform: rotate(180deg); }
        .faq-answer {
            padding: 0 20px;
            max-height: 0;
            overflow: hidden;
            transition: var(--transition);
            color: var(--text-mid);
            line-height: 1.7;
            font-size: 0.95rem;
        }
        .faq-item.active .faq-answer { padding: 0 20px 20px; max-height: 400px; }

        /* ===== CTA ===== */
        .cta-section {
            background: var(--primary);
            color: #fff;
            text-align: center;
            padding: var(--sp-lg) 0;
        }
        .cta-section h2 { color: #fff; font-size: 2rem; margin-bottom: 6px; }
        .cta-section p { color: rgba(255,255,255,0.75); margin-bottom: var(--sp-sm); font-size: 1.1rem; }
        .cta-section .btn-primary { background: #fff; color: var(--primary); border-color: #fff; box-shadow: 0 4px 20px rgba(0,0,0,0.15); }
        .cta-section .btn-primary:hover { background: var(--secondary); color: var(--primary-dark); border-color: var(--secondary); }

        /* ===== Footer ===== */
        .site-footer {
            background: var(--bg-dark);
            color: rgba(255,255,255,0.65);
            padding: var(--sp-lg) 0 var(--sp-md);
        }
        .footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: var(--sp-md); }
        .footer-brand .logo { color: #fff; margin-bottom: var(--sp-sm); }
        .footer-brand .logo span { -webkit-text-fill-color: #fff; background: none; }
        .footer-brand p { font-size: 0.92rem; line-height: 1.7; max-width: 320px; }
        .footer-col h4 { color: #fff; font-size: 1rem; margin-bottom: var(--sp-sm); font-weight: 600; }
        .footer-col a { display: block; color: rgba(255,255,255,0.55); font-size: 0.9rem; padding: 4px 0; }
        .footer-col a:hover { color: #fff; }
        .footer-bottom {
            border-top: 1px solid rgba(255,255,255,0.08);
            margin-top: var(--sp-md);
            padding-top: var(--sp-sm);
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
            gap: var(--sp-sm);
            font-size: 0.88rem;
        }

        /* ===== Tags ===== */
        .tag { display: inline-block; padding: 2px 12px; border-radius: 100px; font-size: 0.8rem; font-weight: 500; background: var(--bg-light); color: var(--text-mid); border: 1px solid var(--border); }

        /* ===== Empty State ===== */
        .empty-state { text-align: center; padding: var(--sp-md); color: var(--text-light); font-size: 1rem; }

        /* ===== Responsive ===== */
        @media (max-width: 1024px) {
            .grid-4 { grid-template-columns: repeat(2, 1fr); }
            .footer-grid { grid-template-columns: 1fr 1fr; }
            .hero-title { font-size: 2.5rem; }
        }
        @media (max-width: 768px) {
            .nav-list { display: none; position: absolute; top: 68px; left: 0; right: 0; background: var(--bg-white); flex-direction: column; padding: var(--sp-sm); border-bottom: 1px solid var(--border); box-shadow: var(--shadow-md); }
            .nav-list.open { display: flex; }
            .nav-list a { width: 100%; padding: 12px 16px; }
            .nav-list a.active::after { display: none; }
            .nav-toggle { display: block; }
            .hero { min-height: 400px; }
            .hero-title { font-size: 2rem; }
            .hero-stats { flex-wrap: wrap; gap: var(--sp-sm); }
            .grid-2, .grid-3 { grid-template-columns: 1fr; }
            .footer-grid { grid-template-columns: 1fr; }
            .section-title { font-size: 1.6rem; }
            .hero-actions .btn { width: 100%; justify-content: center; }
            .category-tabs { flex-wrap: nowrap; overflow-x: auto; padding-bottom: 8px; -webkit-overflow-scrolling: touch; }
            .category-tab { white-space: nowrap; }
        }
        @media (max-width: 520px) {
            .header-inner { height: 60px; }
            .logo { font-size: 1.1rem; }
            .hero-title { font-size: 1.6rem; }
            .hero-desc { font-size: 0.95rem; }
            .btn { padding: 12px 24px; font-size: 0.9rem; }
            .section { padding: var(--sp-md) 0; }
            .container { padding: 0 12px; }
        }

        /* ===== Focus ===== */
        a:focus-visible, button:focus-visible, input:focus-visible { outline: 3px solid var(--accent); outline-offset: 2px; }

        /* ===== Misc ===== */
        .text-center { text-align: center; }
        .mt-sm { margin-top: var(--sp-sm); }
        .mt-md { margin-top: var(--sp-md); }
        .gap-sm { gap: var(--sp-sm); }
        .flex-wrap { flex-wrap: wrap; }
        .badge {
            display: inline-flex;
            align-items: center;
            gap: 4px;
            padding: 2px 12px;
            border-radius: 100px;
            font-size: 0.8rem;
            font-weight: 600;
            background: rgba(6,182,212,0.1);
            color: var(--accent);
        }
        .badge-warning { background: rgba(245,158,11,0.12); color: var(--secondary); }

/* roulang page: category1 */
:root {
    --primary: #1a56db;
    --primary-dark: #0f3a8e;
    --primary-light: #3b82f6;
    --primary-soft: #e8f0fe;
    --secondary: #0ea5e9;
    --accent: #f59e0b;
    --success: #10b981;
    --danger: #ef4444;
    --bg: #ffffff;
    --bg-alt: #f8fafc;
    --bg-card: #ffffff;
    --text: #1e293b;
    --text-soft: #64748b;
    --text-light: #94a3b8;
    --border: #e2e8f0;
    --border-light: #f1f5f9;
    --radius: 12px;
    --radius-sm: 8px;
    --radius-lg: 20px;
    --shadow: 0 4px 24px rgba(0,0,0,0.06);
    --shadow-hover: 0 12px 40px rgba(0,0,0,0.10);
    --shadow-card: 0 2px 16px rgba(0,0,0,0.04);
    --transition: 0.3s cubic-bezier(0.4,0,0.2,1);
    --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --max-width: 1200px;
    --header-h: 72px;
}
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{font-family:var(--font);font-size:16px;line-height:1.7;color:var(--text);background:var(--bg);-webkit-font-smoothing:antialiased}
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}
button,input,textarea{font-family:inherit;font-size:inherit;outline:none}
ul,ol{list-style:none}
.container{width:100%;max-width:var(--max-width);margin:0 auto;padding:0 24px}
@media(max-width:768px){.container{padding:0 16px}}

/* header */
.site-header{position:sticky;top:0;z-index:100;background:rgba(255,255,255,0.96);backdrop-filter:blur(12px);border-bottom:1px solid var(--border);height:var(--header-h)}
.header-inner{display:flex;align-items:center;justify-content:space-between;height:100%;max-width:var(--max-width);margin:0 auto;padding:0 24px}
.logo{display:flex;align-items:center;gap:10px;font-weight:700;font-size:20px;color:var(--text)!important}
.logo i{color:var(--primary);font-size:24px}
.logo span{background:linear-gradient(135deg,var(--primary),var(--secondary));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.nav-toggle{display:none;background:none;border:none;font-size:22px;color:var(--text);cursor:pointer;padding:8px}
.nav-list{display:flex;align-items:center;gap:6px}
.nav-list a{position:relative;padding:8px 18px;border-radius:var(--radius-sm);font-size:15px;font-weight:500;color:var(--text-soft);transition:all var(--transition)}
.nav-list a:hover{color:var(--primary);background:var(--primary-soft)}
.nav-list a.active{color:var(--primary);background:var(--primary-soft);font-weight:600}
.nav-list a.active::after{content:'';position:absolute;bottom:2px;left:50%;transform:translateX(-50%);width:20px;height:3px;background:var(--primary);border-radius:4px}
.nav-cta{background:linear-gradient(135deg,var(--primary),var(--primary-dark))!important;color:#fff!important;padding:8px 22px!important;border-radius:var(--radius-sm)!important;font-weight:600!important;display:flex;align-items:center;gap:8px}
.nav-cta:hover{transform:translateY(-1px);box-shadow:0 6px 20px rgba(26,86,219,0.35)!important;color:#fff!important}
.nav-cta i{font-size:14px}
@media(max-width:768px){
    .nav-toggle{display:block}
    .nav-list{position:fixed;top:var(--header-h);left:0;right:0;background:#fff;flex-direction:column;padding:16px 24px 24px;gap:4px;border-bottom:2px solid var(--border);box-shadow:var(--shadow);transform:translateY(-120%);opacity:0;pointer-events:none;transition:all 0.4s ease}
    .nav-list.open{transform:translateY(0);opacity:1;pointer-events:auto}
    .nav-list a{width:100%;padding:12px 16px;font-size:16px}
    .nav-list a.active::after{display:none}
    .nav-cta{margin-top:8px;justify-content:center}
}

/* page banner */
.page-banner{position:relative;padding:80px 0 60px;background:linear-gradient(135deg,#0f172a 0%,#1e293b 50%,#0f3a8e 100%);overflow:hidden;min-height:320px;display:flex;align-items:center}
.page-banner::before{content:'';position:absolute;inset:0;background:url('/assets/images/backpic/back-1.png') center/cover no-repeat;opacity:0.15;mix-blend-mode:overlay}
.page-banner::after{content:'';position:absolute;inset:0;background:radial-gradient(ellipse at top right,rgba(59,130,246,0.2),transparent 60%)}
.banner-content{position:relative;z-index:2;text-align:center;max-width:800px;margin:0 auto}
.banner-content h1{font-size:42px;font-weight:800;color:#fff;line-height:1.2;margin-bottom:16px;letter-spacing:-0.5px}
.banner-content h1 i{color:var(--secondary);margin-right:10px}
.banner-content p{font-size:18px;color:rgba(255,255,255,0.75);max-width:640px;margin:0 auto 24px;line-height:1.7}
.banner-tags{display:flex;flex-wrap:wrap;gap:10px;justify-content:center}
.banner-tags span{display:inline-flex;align-items:center;gap:6px;background:rgba(255,255,255,0.12);backdrop-filter:blur(4px);border:1px solid rgba(255,255,255,0.15);color:#fff;padding:6px 16px;border-radius:40px;font-size:14px;font-weight:400}
.banner-tags span i{color:var(--secondary);font-size:12px}
@media(max-width:768px){
    .page-banner{padding:60px 0 48px;min-height:260px}
    .banner-content h1{font-size:28px}
    .banner-content p{font-size:16px}
}
@media(max-width:520px){
    .page-banner{padding:48px 0 36px;min-height:220px}
    .banner-content h1{font-size:24px}
    .banner-content p{font-size:15px}
}

/* breadcrumb */
.breadcrumb{background:var(--bg-alt);border-bottom:1px solid var(--border);padding:12px 0;font-size:14px;color:var(--text-soft)}
.breadcrumb .container{display:flex;align-items:center;gap:8px;flex-wrap:wrap}
.breadcrumb a{color:var(--text-soft)}
.breadcrumb a:hover{color:var(--primary)}
.breadcrumb .sep{color:var(--text-light)}
.breadcrumb .current{color:var(--text);font-weight:500}

/* section common */
.section{padding:72px 0}
.section-alt{background:var(--bg-alt)}
.section-header{text-align:center;margin-bottom:48px}
.section-header .tag{display:inline-flex;align-items:center;gap:6px;background:var(--primary-soft);color:var(--primary);padding:4px 16px;border-radius:40px;font-size:13px;font-weight:600;margin-bottom:12px}
.section-header .tag i{font-size:12px}
.section-header h2{font-size:32px;font-weight:700;color:var(--text);margin-bottom:12px;letter-spacing:-0.3px}
.section-header p{font-size:17px;color:var(--text-soft);max-width:600px;margin:0 auto;line-height:1.7}
@media(max-width:768px){
    .section{padding:48px 0}
    .section-header h2{font-size:26px}
    .section-header p{font-size:15px}
}

/* guide step cards */
.guide-steps{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}
.guide-card{background:var(--bg-card);border-radius:var(--radius);padding:32px 28px;box-shadow:var(--shadow-card);border:1px solid var(--border);transition:all var(--transition);position:relative;overflow:hidden}
.guide-card::before{content:'';position:absolute;top:0;left:0;right:0;height:4px;background:linear-gradient(90deg,var(--primary),var(--secondary));opacity:0;transition:opacity var(--transition)}
.guide-card:hover::before{opacity:1}
.guide-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-hover);border-color:var(--primary-light)}
.guide-card .step-num{position:absolute;top:20px;right:24px;font-size:48px;font-weight:800;color:var(--border-light);line-height:1;user-select:none}
.guide-card .icon{width:52px;height:52px;border-radius:12px;display:flex;align-items:center;justify-content:center;font-size:24px;margin-bottom:18px;position:relative;z-index:1}
.guide-card .icon.blue{background:var(--primary-soft);color:var(--primary)}
.guide-card .icon.green{background:#ecfdf5;color:var(--success)}
.guide-card .icon.amber{background:#fffbeb;color:var(--accent)}
.guide-card h3{font-size:20px;font-weight:700;margin-bottom:10px;position:relative;z-index:1}
.guide-card p{font-size:15px;color:var(--text-soft);line-height:1.7;position:relative;z-index:1}
.guide-card ul{margin-top:12px;position:relative;z-index:1}
.guide-card ul li{font-size:14px;color:var(--text-soft);padding:4px 0;padding-left:20px;position:relative}
.guide-card ul li::before{content:'✓';position:absolute;left:0;color:var(--success);font-weight:700}
@media(max-width:1024px){
    .guide-steps{grid-template-columns:repeat(2,1fr)}
}
@media(max-width:640px){
    .guide-steps{grid-template-columns:1fr}
    .guide-card{padding:24px 20px}
}

/* methods grid */
.methods-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px}
.method-card{background:var(--bg-card);border-radius:var(--radius);padding:28px 20px;text-align:center;border:1px solid var(--border);box-shadow:var(--shadow-card);transition:all var(--transition)}
.method-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-hover);border-color:var(--primary-light)}
.method-card .icon-wrap{width:64px;height:64px;border-radius:50%;display:flex;align-items:center;justify-content:center;margin:0 auto 16px;font-size:26px}
.method-card .icon-wrap.blue{background:var(--primary-soft);color:var(--primary)}
.method-card .icon-wrap.green{background:#ecfdf5;color:var(--success)}
.method-card .icon-wrap.purple{background:#f3e8ff;color:#7c3aed}
.method-card .icon-wrap.amber{background:#fffbeb;color:var(--accent)}
.method-card h4{font-size:17px;font-weight:600;margin-bottom:8px}
.method-card p{font-size:14px;color:var(--text-soft);line-height:1.6}
@media(max-width:1024px){
    .methods-grid{grid-template-columns:repeat(2,1fr)}
}
@media(max-width:520px){
    .methods-grid{grid-template-columns:1fr}
}

/* problem list */
.problem-list{display:grid;grid-template-columns:repeat(2,1fr);gap:20px}
.problem-item{background:var(--bg-card);border-radius:var(--radius-sm);padding:20px 24px;border:1px solid var(--border);display:flex;align-items:flex-start;gap:14px;transition:all var(--transition)}
.problem-item:hover{border-color:var(--primary-light);box-shadow:var(--shadow-card)}
.problem-item .q-icon{flex-shrink:0;width:36px;height:36px;border-radius:50%;background:var(--primary-soft);color:var(--primary);display:flex;align-items:center;justify-content:center;font-size:15px;font-weight:700}
.problem-item .q-content h4{font-size:16px;font-weight:600;margin-bottom:4px}
.problem-item .q-content p{font-size:14px;color:var(--text-soft);line-height:1.6}
@media(max-width:768px){
    .problem-list{grid-template-columns:1fr}
}

/* faq */
.faq-list{max-width:800px;margin:0 auto;display:flex;flex-direction:column;gap:12px}
.faq-item{border:1px solid var(--border);border-radius:var(--radius-sm);overflow:hidden;transition:all var(--transition)}
.faq-item:hover{border-color:var(--primary-light)}
.faq-q{display:flex;align-items:center;justify-content:space-between;padding:16px 20px;cursor:pointer;background:var(--bg-card);font-weight:500;font-size:16px;transition:background var(--transition);gap:12px}
.faq-q:hover{background:var(--primary-soft)}
.faq-q i{font-size:14px;color:var(--text-light);transition:transform var(--transition);flex-shrink:0}
.faq-item.open .faq-q i{transform:rotate(180deg);color:var(--primary)}
.faq-a{padding:0 20px;max-height:0;overflow:hidden;transition:all 0.35s ease;background:var(--bg-card);border-top:0 solid transparent}
.faq-item.open .faq-a{padding:16px 20px 20px;max-height:300px;border-top-width:1px;border-top-color:var(--border)}
.faq-a p{font-size:15px;color:var(--text-soft);line-height:1.7}
.faq-a p + p{margin-top:8px}

/* cta */
.cta-section{background:linear-gradient(135deg,#0f172a,#1e293b);padding:72px 0;text-align:center;position:relative;overflow:hidden}
.cta-section::before{content:'';position:absolute;inset:0;background:url('/assets/images/backpic/back-2.png') center/cover no-repeat;opacity:0.08;mix-blend-mode:overlay}
.cta-section .container{position:relative;z-index:2}
.cta-section h2{font-size:34px;font-weight:800;color:#fff;margin-bottom:16px}
.cta-section p{font-size:17px;color:rgba(255,255,255,0.7);max-width:560px;margin:0 auto 28px}
.cta-btns{display:flex;flex-wrap:wrap;gap:14px;justify-content:center}
.cta-btn{display:inline-flex;align-items:center;gap:10px;padding:14px 34px;border-radius:var(--radius-sm);font-weight:600;font-size:16px;transition:all var(--transition);border:none;cursor:pointer}
.cta-btn.primary{background:linear-gradient(135deg,var(--primary),var(--primary-dark));color:#fff}
.cta-btn.primary:hover{transform:translateY(-2px);box-shadow:0 10px 32px rgba(26,86,219,0.4)}
.cta-btn.outline{background:transparent;border:2px solid rgba(255,255,255,0.3);color:#fff}
.cta-btn.outline:hover{background:rgba(255,255,255,0.1);border-color:rgba(255,255,255,0.6);transform:translateY(-2px)}
@media(max-width:640px){
    .cta-section h2{font-size:26px}
    .cta-btn{padding:12px 24px;font-size:15px}
}

/* footer */
.site-footer{background:#0f172a;color:rgba(255,255,255,0.7);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{color:#fff!important;margin-bottom:16px;font-size:18px}
.footer-brand .logo i{color:var(--secondary)}
.footer-brand p{font-size:14px;line-height:1.8;max-width:360px}
.footer-col h4{color:#fff;font-size:16px;font-weight:600;margin-bottom:16px}
.footer-col a{display:block;color:rgba(255,255,255,0.6);font-size:14px;padding:4px 0;transition:all var(--transition)}
.footer-col a:hover{color:var(--secondary);padding-left:4px}
.footer-bottom{display:flex;flex-wrap:wrap;justify-content:space-between;align-items:center;padding:20px 0;font-size:13px;color:rgba(255,255,255,0.4);gap:12px}
.footer-bottom i{margin-right:4px}
@media(max-width:1024px){
    .footer-grid{grid-template-columns:1fr 1fr;gap:32px}
}
@media(max-width:640px){
    .footer-grid{grid-template-columns:1fr;gap:24px}
    .footer-bottom{flex-direction:column;text-align:center}
}

/* utilities */
.text-center{text-align:center}
.mb-12{margin-bottom:12px}
.mb-24{margin-bottom:24px}
.mb-48{margin-bottom:48px}
.mt-48{margin-top:48px}
.gap-8{gap:8px}
.flex-center{display:flex;align-items:center;justify-content:center}
.tag-sm{display:inline-flex;align-items:center;gap:4px;background:var(--primary-soft);color:var(--primary);padding:2px 12px;border-radius:40px;font-size:12px;font-weight:500}

/* roulang page: article */
/* ===== Design Variables ===== */
        :root {
            --clr-primary: #2563eb;
            --clr-primary-dark: #1d4ed8;
            --clr-primary-light: #dbeafe;
            --clr-secondary: #0ea5e9;
            --clr-accent: #f59e0b;
            --clr-success: #10b981;
            --clr-bg: #f0f4f8;
            --clr-surface: #ffffff;
            --clr-text: #0f172a;
            --clr-text-secondary: #475569;
            --clr-text-muted: #94a3b8;
            --clr-border: #e2e8f0;
            --clr-border-light: #f1f5f9;
            --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, 0.07);
            --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.10);
            --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
            --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
            --container-max: 1200px;
            --header-height: 72px;
        }

        /* ===== Reset & Base ===== */
        *,
        *::before,
        *::after {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }
        html {
            scroll-behavior: smooth;
        }
        body {
            font-family: var(--font-family);
            font-size: 16px;
            line-height: 1.7;
            color: var(--clr-text);
            background: var(--clr-bg);
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }
        a {
            color: var(--clr-primary);
            text-decoration: none;
            transition: color var(--transition);
        }
        a:hover {
            color: var(--clr-primary-dark);
        }
        a:focus-visible {
            outline: 2px solid var(--clr-primary);
            outline-offset: 2px;
            border-radius: 4px;
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
        }
        button,
        input,
        textarea,
        select {
            font-family: inherit;
            font-size: inherit;
            line-height: 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(--clr-text);
        }
        p {
            margin-bottom: 1em;
        }
        p:last-child {
            margin-bottom: 0;
        }

        /* ===== Container ===== */
        .container {
            max-width: var(--container-max);
            margin: 0 auto;
            padding: 0 24px;
        }
        @media (max-width: 768px) {
            .container {
                padding: 0 16px;
            }
        }

        /* ===== Header / Navigation ===== */
        .site-header {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            height: var(--header-height);
            background: rgba(255, 255, 255, 0.92);
            backdrop-filter: blur(16px);
            -webkit-backdrop-filter: blur(16px);
            border-bottom: 1px solid var(--clr-border);
            z-index: 1000;
            box-shadow: 0 1px 8px rgba(0, 0, 0, 0.04);
        }
        .header-inner {
            max-width: var(--container-max);
            margin: 0 auto;
            padding: 0 24px;
            height: 100%;
            display: flex;
            align-items: center;
            justify-content: space-between;
        }
        .logo {
            display: flex;
            align-items: center;
            gap: 10px;
            font-size: 1.25rem;
            font-weight: 700;
            color: var(--clr-text);
        }
        .logo i {
            color: var(--clr-primary);
            font-size: 1.5rem;
        }
        .logo span {
            background: linear-gradient(135deg, var(--clr-primary), var(--clr-secondary));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        .logo:hover {
            color: var(--clr-text);
        }
        .nav-list {
            display: flex;
            align-items: center;
            gap: 6px;
        }
        .nav-list a {
            display: inline-flex;
            align-items: center;
            gap: 6px;
            padding: 8px 18px;
            border-radius: var(--radius-sm);
            font-weight: 500;
            font-size: 0.95rem;
            color: var(--clr-text-secondary);
            transition: all var(--transition);
            position: relative;
        }
        .nav-list a:hover {
            color: var(--clr-primary);
            background: var(--clr-primary-light);
        }
        .nav-list a.active {
            color: var(--clr-primary);
            background: var(--clr-primary-light);
            font-weight: 600;
        }
        .nav-list a.active::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 50%;
            transform: translateX(-50%);
            width: 20px;
            height: 3px;
            border-radius: 3px;
            background: var(--clr-primary);
        }
        .nav-list a.nav-cta {
            background: var(--clr-primary);
            color: #fff;
            padding: 8px 22px;
            border-radius: var(--radius-sm);
            font-weight: 600;
            box-shadow: 0 2px 10px rgba(37, 99, 235, 0.30);
        }
        .nav-list a.nav-cta:hover {
            background: var(--clr-primary-dark);
            box-shadow: 0 4px 16px rgba(37, 99, 235, 0.40);
            color: #fff;
        }
        .nav-toggle {
            display: none;
            font-size: 1.4rem;
            color: var(--clr-text);
            padding: 8px;
            border-radius: var(--radius-sm);
            transition: background var(--transition);
        }
        .nav-toggle:hover {
            background: var(--clr-border-light);
        }
        @media (max-width: 768px) {
            .nav-toggle {
                display: block;
            }
            .nav-list {
                position: fixed;
                top: var(--header-height);
                left: 0;
                right: 0;
                background: rgba(255, 255, 255, 0.98);
                backdrop-filter: blur(16px);
                -webkit-backdrop-filter: blur(16px);
                flex-direction: column;
                padding: 16px 24px 24px;
                gap: 8px;
                border-bottom: 1px solid var(--clr-border);
                box-shadow: var(--shadow-md);
                transform: translateY(-120%);
                opacity: 0;
                pointer-events: none;
                transition: all 0.35s ease;
            }
            .nav-list.open {
                transform: translateY(0);
                opacity: 1;
                pointer-events: auto;
            }
            .nav-list a {
                width: 100%;
                justify-content: center;
                padding: 12px 18px;
                font-size: 1rem;
            }
            .nav-list a.nav-cta {
                margin-top: 4px;
            }
            .nav-list a.active::after {
                display: none;
            }
        }

        /* ===== Hero / Banner ===== */
        .article-hero {
            margin-top: var(--header-height);
            position: relative;
            min-height: 320px;
            display: flex;
            align-items: center;
            justify-content: center;
            text-align: center;
            background: linear-gradient(135deg, rgba(37, 99, 235, 0.88), rgba(14, 165, 233, 0.82)), url('/assets/images/backpic/back-1.png') center center / cover no-repeat;
            padding: 60px 24px;
        }
        .article-hero .hero-content {
            max-width: 800px;
            position: relative;
            z-index: 2;
        }
        .article-hero .hero-category {
            display: inline-block;
            padding: 4px 16px;
            border-radius: 50px;
            background: rgba(255, 255, 255, 0.20);
            backdrop-filter: blur(4px);
            color: #fff;
            font-size: 0.85rem;
            font-weight: 500;
            letter-spacing: 0.5px;
            margin-bottom: 16px;
            border: 1px solid rgba(255, 255, 255, 0.25);
        }
        .article-hero h1 {
            font-size: 2.4rem;
            font-weight: 800;
            color: #fff;
            line-height: 1.3;
            text-shadow: 0 2px 12px rgba(0, 0, 0, 0.15);
            margin-bottom: 16px;
        }
        .article-hero .hero-desc {
            font-size: 1.1rem;
            color: rgba(255, 255, 255, 0.90);
            max-width: 640px;
            margin: 0 auto;
            line-height: 1.6;
        }
        @media (max-width: 768px) {
            .article-hero {
                min-height: 240px;
                padding: 40px 16px;
            }
            .article-hero h1 {
                font-size: 1.6rem;
            }
            .article-hero .hero-desc {
                font-size: 0.95rem;
            }
        }
        @media (max-width: 520px) {
            .article-hero h1 {
                font-size: 1.3rem;
            }
        }

        /* ===== Article Main ===== */
        .article-main {
            padding: 48px 0 32px;
        }
        .article-layout {
            display: grid;
            grid-template-columns: 1fr 320px;
            gap: 40px;
            align-items: start;
        }
        @media (max-width: 1024px) {
            .article-layout {
                grid-template-columns: 1fr;
                gap: 32px;
            }
        }

        /* ===== Article Body ===== */
        .article-body {
            background: var(--clr-surface);
            border-radius: var(--radius-md);
            box-shadow: var(--shadow-md);
            padding: 40px;
            overflow: hidden;
        }
        .article-meta {
            display: flex;
            flex-wrap: wrap;
            align-items: center;
            gap: 12px 24px;
            margin-bottom: 28px;
            padding-bottom: 20px;
            border-bottom: 1px solid var(--clr-border-light);
            font-size: 0.9rem;
            color: var(--clr-text-secondary);
        }
        .article-meta .meta-item {
            display: inline-flex;
            align-items: center;
            gap: 6px;
        }
        .article-meta .meta-item i {
            color: var(--clr-primary);
            font-size: 0.85rem;
        }
        .article-meta .meta-category {
            display: inline-block;
            padding: 2px 14px;
            border-radius: 50px;
            background: var(--clr-primary-light);
            color: var(--clr-primary);
            font-size: 0.8rem;
            font-weight: 600;
        }
        .article-cover {
            border-radius: var(--radius-sm);
            overflow: hidden;
            margin-bottom: 32px;
            box-shadow: var(--shadow-sm);
        }
        .article-cover img {
            width: 100%;
            aspect-ratio: 16 / 7;
            object-fit: cover;
        }
        .article-content {
            font-size: 1.05rem;
            line-height: 1.85;
            color: var(--clr-text);
        }
        .article-content h2,
        .article-content h3,
        .article-content h4 {
            margin-top: 1.8em;
            margin-bottom: 0.6em;
            font-weight: 700;
            color: var(--clr-text);
        }
        .article-content h2 {
            font-size: 1.5rem;
        }
        .article-content h3 {
            font-size: 1.25rem;
        }
        .article-content p {
            margin-bottom: 1.2em;
        }
        .article-content ul,
        .article-content ol {
            margin-bottom: 1.2em;
            padding-left: 1.6em;
        }
        .article-content ul {
            list-style: disc;
        }
        .article-content ol {
            list-style: decimal;
        }
        .article-content li {
            margin-bottom: 0.4em;
        }
        .article-content a {
            color: var(--clr-primary);
            text-decoration: underline;
            text-underline-offset: 3px;
        }
        .article-content a:hover {
            color: var(--clr-primary-dark);
        }
        .article-content img {
            border-radius: var(--radius-sm);
            margin: 1.5em 0;
        }
        .article-content blockquote {
            border-left: 4px solid var(--clr-primary);
            background: var(--clr-primary-light);
            padding: 16px 20px;
            margin: 1.5em 0;
            border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
            color: var(--clr-text-secondary);
            font-style: normal;
        }
        .article-content code {
            background: #f1f5f9;
            padding: 2px 10px;
            border-radius: 4px;
            font-size: 0.9em;
            font-family: 'SF Mono', 'Fira Code', monospace;
        }
        .article-content pre {
            background: #1e293b;
            color: #e2e8f0;
            padding: 20px 24px;
            border-radius: var(--radius-sm);
            overflow-x: auto;
            font-size: 0.9rem;
            line-height: 1.6;
            margin: 1.5em 0;
        }
        .article-content pre code {
            background: none;
            padding: 0;
            color: inherit;
            font-size: inherit;
        }
        .article-footer-meta {
            margin-top: 32px;
            padding-top: 20px;
            border-top: 1px solid var(--clr-border-light);
            display: flex;
            flex-wrap: wrap;
            align-items: center;
            justify-content: space-between;
            gap: 12px;
        }
        .article-tags {
            display: flex;
            flex-wrap: wrap;
            gap: 8px;
        }
        .article-tags .tag {
            display: inline-block;
            padding: 4px 14px;
            border-radius: 50px;
            background: var(--clr-bg);
            color: var(--clr-text-secondary);
            font-size: 0.8rem;
            font-weight: 500;
            transition: all var(--transition);
        }
        .article-tags .tag:hover {
            background: var(--clr-primary-light);
            color: var(--clr-primary);
        }
        .article-share {
            display: flex;
            align-items: center;
            gap: 8px;
            font-size: 0.85rem;
            color: var(--clr-text-muted);
        }
        .article-share a {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            width: 36px;
            height: 36px;
            border-radius: 50%;
            background: var(--clr-bg);
            color: var(--clr-text-secondary);
            transition: all var(--transition);
            font-size: 0.95rem;
        }
        .article-share a:hover {
            background: var(--clr-primary-light);
            color: var(--clr-primary);
        }
        @media (max-width: 768px) {
            .article-body {
                padding: 24px 16px;
            }
            .article-meta {
                gap: 8px 16px;
                font-size: 0.85rem;
            }
            .article-content {
                font-size: 1rem;
            }
            .article-cover img {
                aspect-ratio: 16 / 9;
            }
        }

        /* ===== Sidebar ===== */
        .article-sidebar {
            display: flex;
            flex-direction: column;
            gap: 28px;
        }
        .sidebar-card {
            background: var(--clr-surface);
            border-radius: var(--radius-md);
            box-shadow: var(--shadow-md);
            padding: 24px;
        }
        .sidebar-card h3 {
            font-size: 1.05rem;
            font-weight: 700;
            margin-bottom: 16px;
            display: flex;
            align-items: center;
            gap: 8px;
        }
        .sidebar-card h3 i {
            color: var(--clr-primary);
        }
        .sidebar-list {
            display: flex;
            flex-direction: column;
            gap: 12px;
        }
        .sidebar-list a {
            display: flex;
            align-items: flex-start;
            gap: 12px;
            padding: 10px 14px;
            border-radius: var(--radius-sm);
            background: var(--clr-bg);
            transition: all var(--transition);
            font-size: 0.9rem;
            color: var(--clr-text-secondary);
        }
        .sidebar-list a:hover {
            background: var(--clr-primary-light);
            color: var(--clr-primary);
        }
        .sidebar-list a .num {
            flex-shrink: 0;
            width: 26px;
            height: 26px;
            border-radius: 50%;
            background: var(--clr-primary);
            color: #fff;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 0.75rem;
            font-weight: 700;
        }
        .sidebar-list a .text {
            flex: 1;
            line-height: 1.4;
        }
        .sidebar-cta {
            background: linear-gradient(135deg, var(--clr-primary), var(--clr-secondary));
            color: #fff;
            border-radius: var(--radius-md);
            padding: 28px 24px;
            text-align: center;
        }
        .sidebar-cta h4 {
            color: #fff;
            font-size: 1.1rem;
            margin-bottom: 8px;
        }
        .sidebar-cta p {
            font-size: 0.9rem;
            opacity: 0.90;
            margin-bottom: 16px;
        }
        .sidebar-cta .btn-white {
            display: inline-block;
            padding: 10px 28px;
            border-radius: var(--radius-sm);
            background: #fff;
            color: var(--clr-primary);
            font-weight: 600;
            font-size: 0.9rem;
            transition: all var(--transition);
            box-shadow: 0 2px 12px rgba(0, 0, 0, 0.10);
        }
        .sidebar-cta .btn-white:hover {
            transform: translateY(-2px);
            box-shadow: 0 6px 20px rgba(0, 0, 0, 0.15);
            color: var(--clr-primary-dark);
        }
        @media (max-width: 1024px) {
            .article-sidebar {
                display: grid;
                grid-template-columns: 1fr 1fr;
                gap: 20px;
            }
        }
        @media (max-width: 640px) {
            .article-sidebar {
                grid-template-columns: 1fr;
            }
        }

        /* ===== Not Found ===== */
        .not-found-box {
            text-align: center;
            padding: 80px 24px;
            background: var(--clr-surface);
            border-radius: var(--radius-md);
            box-shadow: var(--shadow-md);
        }
        .not-found-box i {
            font-size: 3.5rem;
            color: var(--clr-text-muted);
            margin-bottom: 20px;
        }
        .not-found-box h2 {
            font-size: 1.6rem;
            color: var(--clr-text);
            margin-bottom: 12px;
        }
        .not-found-box p {
            color: var(--clr-text-secondary);
            margin-bottom: 24px;
        }
        .not-found-box .btn-home {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 12px 32px;
            border-radius: var(--radius-sm);
            background: var(--clr-primary);
            color: #fff;
            font-weight: 600;
            transition: all var(--transition);
        }
        .not-found-box .btn-home:hover {
            background: var(--clr-primary-dark);
            transform: translateY(-2px);
            box-shadow: 0 6px 20px rgba(37, 99, 235, 0.35);
            color: #fff;
        }

        /* ===== Related Section ===== */
        .related-section {
            padding: 48px 0 40px;
        }
        .related-section .section-title {
            font-size: 1.6rem;
            font-weight: 700;
            margin-bottom: 32px;
            text-align: center;
            position: relative;
        }
        .related-section .section-title::after {
            content: '';
            display: block;
            width: 50px;
            height: 4px;
            border-radius: 4px;
            background: var(--clr-primary);
            margin: 12px auto 0;
        }
        .related-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 24px;
        }
        .related-card {
            background: var(--clr-surface);
            border-radius: var(--radius-md);
            box-shadow: var(--shadow-md);
            overflow: hidden;
            transition: all var(--transition);
        }
        .related-card:hover {
            transform: translateY(-4px);
            box-shadow: var(--shadow-lg);
        }
        .related-card .card-img {
            aspect-ratio: 16 / 10;
            overflow: hidden;
        }
        .related-card .card-img img {
            width: 100%;
            height: 100%;
            object-fit: cover;
            transition: transform 0.4s ease;
        }
        .related-card:hover .card-img img {
            transform: scale(1.05);
        }
        .related-card .card-body {
            padding: 18px 20px 22px;
        }
        .related-card .card-body .card-cat {
            display: inline-block;
            padding: 2px 12px;
            border-radius: 50px;
            background: var(--clr-primary-light);
            color: var(--clr-primary);
            font-size: 0.75rem;
            font-weight: 600;
            margin-bottom: 10px;
        }
        .related-card .card-body h4 {
            font-size: 1.05rem;
            font-weight: 600;
            margin-bottom: 8px;
            line-height: 1.4;
            display: -webkit-box;
            -webkit-line-clamp: 2;
            -webkit-box-orient: vertical;
            overflow: hidden;
        }
        .related-card .card-body h4 a {
            color: var(--clr-text);
        }
        .related-card .card-body h4 a:hover {
            color: var(--clr-primary);
        }
        .related-card .card-body .card-desc {
            font-size: 0.88rem;
            color: var(--clr-text-secondary);
            display: -webkit-box;
            -webkit-line-clamp: 2;
            -webkit-box-orient: vertical;
            overflow: hidden;
            margin-bottom: 12px;
        }
        .related-card .card-body .card-meta {
            font-size: 0.8rem;
            color: var(--clr-text-muted);
            display: flex;
            align-items: center;
            gap: 16px;
        }
        .related-card .card-body .card-meta i {
            margin-right: 4px;
        }
        @media (max-width: 1024px) {
            .related-grid {
                grid-template-columns: repeat(2, 1fr);
            }
        }
        @media (max-width: 640px) {
            .related-grid {
                grid-template-columns: 1fr;
            }
            .related-section .section-title {
                font-size: 1.3rem;
            }
        }

        /* ===== CTA Section ===== */
        .cta-section {
            padding: 60px 24px;
            background: linear-gradient(135deg, var(--clr-primary), #1e40af);
            text-align: center;
            color: #fff;
            margin-top: 8px;
        }
        .cta-section h2 {
            font-size: 1.8rem;
            color: #fff;
            margin-bottom: 12px;
        }
        .cta-section p {
            font-size: 1.05rem;
            opacity: 0.92;
            max-width: 600px;
            margin: 0 auto 28px;
        }
        .cta-section .cta-btns {
            display: flex;
            flex-wrap: wrap;
            justify-content: center;
            gap: 16px;
        }
        .cta-section .btn-cta-primary {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 14px 36px;
            border-radius: var(--radius-sm);
            background: #fff;
            color: var(--clr-primary);
            font-weight: 700;
            font-size: 1rem;
            transition: all var(--transition);
            box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
        }
        .cta-section .btn-cta-primary:hover {
            transform: translateY(-3px);
            box-shadow: 0 8px 28px rgba(0, 0, 0, 0.25);
            color: var(--clr-primary-dark);
        }
        .cta-section .btn-cta-secondary {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 14px 36px;
            border-radius: var(--radius-sm);
            background: transparent;
            color: #fff;
            font-weight: 600;
            font-size: 1rem;
            border: 2px solid rgba(255, 255, 255, 0.40);
            transition: all var(--transition);
        }
        .cta-section .btn-cta-secondary:hover {
            background: rgba(255, 255, 255, 0.12);
            border-color: rgba(255, 255, 255, 0.70);
        }
        @media (max-width: 640px) {
            .cta-section {
                padding: 40px 16px;
            }
            .cta-section h2 {
                font-size: 1.3rem;
            }
            .cta-section .btn-cta-primary,
            .cta-section .btn-cta-secondary {
                width: 100%;
                justify-content: center;
            }
        }

        /* ===== Footer ===== */
        .site-footer {
            background: #0f172a;
            color: rgba(255, 255, 255, 0.80);
            padding: 56px 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 {
            color: #fff;
            font-size: 1.2rem;
            margin-bottom: 16px;
        }
        .footer-brand .logo i {
            color: var(--clr-secondary);
        }
        .footer-brand .logo span {
            background: linear-gradient(135deg, #60a5fa, #38bdf8);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        .footer-brand p {
            font-size: 0.9rem;
            color: rgba(255, 255, 255, 0.60);
            line-height: 1.7;
            max-width: 360px;
        }
        .footer-col h4 {
            color: #fff;
            font-size: 0.95rem;
            font-weight: 600;
            margin-bottom: 16px;
            letter-spacing: 0.5px;
        }
        .footer-col a {
            display: block;
            color: rgba(255, 255, 255, 0.60);
            font-size: 0.88rem;
            padding: 5px 0;
            transition: all var(--transition);
        }
        .footer-col a:hover {
            color: #fff;
            padding-left: 4px;
        }
        .footer-bottom {
            display: flex;
            flex-wrap: wrap;
            justify-content: space-between;
            align-items: center;
            padding: 20px 0;
            font-size: 0.82rem;
            color: rgba(255, 255, 255, 0.45);
            gap: 12px;
        }
        .footer-bottom i {
            margin-right: 6px;
        }
        @media (max-width: 1024px) {
            .footer-grid {
                grid-template-columns: 1fr 1fr;
                gap: 32px;
            }
            .footer-brand {
                grid-column: 1 / -1;
            }
        }
        @media (max-width: 640px) {
            .footer-grid {
                grid-template-columns: 1fr;
                gap: 24px;
            }
            .footer-bottom {
                flex-direction: column;
                text-align: center;
            }
        }

        /* ===== Utility ===== */
        .text-center {
            text-align: center;
        }
        .mt-16 {
            margin-top: 16px;
        }
        .mt-32 {
            margin-top: 32px;
        }
        .mb-16 {
            margin-bottom: 16px;
        }
        .mb-32 {
            margin-bottom: 32px;
        }

        /* ===== Back to top ===== */
        .back-top {
            position: fixed;
            bottom: 32px;
            right: 32px;
            width: 48px;
            height: 48px;
            border-radius: 50%;
            background: var(--clr-primary);
            color: #fff;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.2rem;
            box-shadow: var(--shadow-md);
            z-index: 999;
            transition: all var(--transition);
            opacity: 0;
            pointer-events: none;
            transform: translateY(20px);
        }
        .back-top.visible {
            opacity: 1;
            pointer-events: auto;
            transform: translateY(0);
        }
        .back-top:hover {
            background: var(--clr-primary-dark);
            transform: translateY(-4px);
            box-shadow: var(--shadow-lg);
        }

        /* ===== Responsive extras ===== */
        @media (max-width: 520px) {
            .article-meta {
                flex-direction: column;
                align-items: flex-start;
                gap: 6px;
            }
            .article-footer-meta {
                flex-direction: column;
                align-items: flex-start;
            }
        }