:root {
            --primary: #1a3c6e;
            --primary-light: #2a5caa;
            --accent: #e87400;
            --accent-hover: #c96000;
            --bg: #ffffff;
            --bg-light: #f5f7fa;
            --bg-dark: #0f1f3a;
            --text: #2d2d2d;
            --text-light: #666;
            --text-inverse: #ffffff;
            --border: #e0e4e8;
            --shadow: 0 2px 8px rgba(0,0,0,0.08);
            --shadow-lg: 0 8px 32px rgba(0,0,0,0.12);
            --radius: 8px;
            --max-width: 1200px;
            --font: 'Segoe UI', system-ui, -apple-system, sans-serif;
        }

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

        body {
            font-family: var(--font);
            color: var(--text);
            line-height: 1.7;
            background: var(--bg);
            -webkit-font-smoothing: antialiased;
        }

        /* ── Header / Nav ── */
        .site-header {
            background: var(--bg);
            border-bottom: 1px solid var(--border);
            position: sticky;
            top: 0;
            z-index: 100;
            padding: 0 20px;
        }
        .header-inner {
            max-width: var(--max-width);
            margin: 0 auto;
            display: flex;
            align-items: center;
            justify-content: space-between;
            height: 64px;
        }
        .logo {
            font-size: 1.4rem;
            font-weight: 700;
            color: var(--primary);
            text-decoration: none;
            letter-spacing: -0.5px;
        }
        .logo span { color: var(--accent); }
        .nav-links {
            display: flex;
            gap: 28px;
            list-style: none;
            align-items: center;
        }
        .nav-links a {
            text-decoration: none;
            color: var(--text);
            font-size: 0.925rem;
            font-weight: 500;
            transition: color .2s;
        }
        .nav-links a:hover { color: var(--primary-light); }
        .nav-cta {
            background: var(--accent);
            color: #fff !important;
            padding: 8px 20px;
            border-radius: 4px;
            font-weight: 600;
            transition: background .2s;
        }
        .nav-cta:hover {
            background: var(--accent-hover);
        }

        /* ── Breadcrumb ── */
        .breadcrumb {
            max-width: var(--max-width);
            margin: 16px auto 0;
            padding: 0 20px;
            font-size: 0.85rem;
            color: var(--text-light);
        }
        .breadcrumb a {
            color: var(--text-light);
            text-decoration: none;
        }
        .breadcrumb a:hover { color: var(--primary-light); text-decoration: underline; }
        .breadcrumb span { margin: 0 6px; }

        /* ── Hero ── */
        .hero {
            background: linear-gradient(135deg, var(--bg-dark) 0%, var(--primary) 100%);
            color: var(--text-inverse);
            padding: 64px 20px 56px;
            text-align: center;
        }
        .hero-inner { max-width: 820px; margin: 0 auto; }
        .hero-badge {
            display: inline-block;
            background: rgba(255,255,255,0.15);
            border: 1px solid rgba(255,255,255,0.25);
            padding: 4px 16px;
            border-radius: 20px;
            font-size: 0.85rem;
            margin-bottom: 20px;
            letter-spacing: 0.5px;
        }
        .hero h1 {
            font-size: 2.5rem;
            font-weight: 800;
            line-height: 1.25;
            margin-bottom: 18px;
            letter-spacing: -0.5px;
        }
        .hero h1 em {
            font-style: normal;
            color: #ffb347;
        }
        .hero-desc {
            font-size: 1.15rem;
            line-height: 1.65;
            opacity: 0.9;
            margin-bottom: 32px;
            max-width: 680px;
            margin-left: auto;
            margin-right: auto;
        }
        .hero-stats {
            display: flex;
            gap: 40px;
            justify-content: center;
            flex-wrap: wrap;
            margin-bottom: 32px;
        }
        .hero-stat {
            text-align: center;
        }
        .hero-stat-num {
            font-size: 2rem;
            font-weight: 800;
            color: #ffb347;
        }
        .hero-stat-label {
            font-size: 0.85rem;
            opacity: 0.8;
            margin-top: 2px;
        }
        .btn {
            display: inline-block;
            padding: 14px 36px;
            border-radius: 6px;
            font-weight: 700;
            font-size: 1rem;
            text-decoration: none;
            border: none;
            cursor: pointer;
            transition: all .2s;
        }
        .btn-primary {
            background: var(--accent);
            color: #fff;
        }
        .btn-primary:hover {
            background: var(--accent-hover);
            box-shadow: 0 4px 16px rgba(232,116,0,0.35);
            transform: translateY(-1px);
        }
        .btn-outline {
            background: transparent;
            color: #fff;
            border: 2px solid rgba(255,255,255,0.5);
            margin-left: 12px;
        }
        .btn-outline:hover {
            border-color: #fff;
            background: rgba(255,255,255,0.08);
        }

        /* ── Sections ── */
        section {
            padding: 64px 20px;
        }
        .section-inner {
            max-width: var(--max-width);
            margin: 0 auto;
        }
        .section-label {
            text-transform: uppercase;
            font-size: 0.8rem;
            font-weight: 700;
            letter-spacing: 1.5px;
            color: var(--accent);
            margin-bottom: 8px;
        }
        h2 {
            font-size: 2rem;
            font-weight: 800;
            color: var(--primary);
            margin-bottom: 16px;
            letter-spacing: -0.5px;
            line-height: 1.25;
        }
        h3 {
            font-size: 1.35rem;
            font-weight: 700;
            color: var(--text);
            margin-bottom: 10px;
        }
        .section-lead {
            font-size: 1.1rem;
            color: var(--text-light);
            max-width: 720px;
            margin-bottom: 40px;
        }

        /* ── Overview ── */
        .overview { background: var(--bg); }
        .overview-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 48px;
            align-items: center;
        }
        .overview-text p {
            margin-bottom: 16px;
            color: var(--text);
        }
        .overview-highlights {
            list-style: none;
            margin-top: 24px;
        }
        .overview-highlights li {
            padding: 6px 0 6px 28px;
            position: relative;
            color: var(--text);
        }
        .overview-highlights li::before {
            content: '✓';
            position: absolute;
            left: 0;
            color: #2e8b57;
            font-weight: 700;
        }
        .overview-image {
            background: var(--bg-light);
            border-radius: var(--radius);
            padding: 40px;
            text-align: center;
            border: 1px solid var(--border);
        }
        .overview-image .placeholder-icon {
            font-size: 5rem;
            opacity: 0.3;
        }
        .overview-image p {
            margin-top: 12px;
            color: var(--text-light);
            font-size: 0.9rem;
        }

        /* ── Features Grid ── */
        .features { background: var(--bg-light); }
        .features-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
            gap: 24px;
        }
        .feature-card {
            background: var(--bg);
            border-radius: var(--radius);
            padding: 28px;
            box-shadow: var(--shadow);
            border: 1px solid var(--border);
            transition: box-shadow .2s;
        }
        .feature-card:hover { box-shadow: var(--shadow-lg); }
        .feature-icon {
            width: 48px;
            height: 48px;
            border-radius: 10px;
            background: var(--bg-light);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.5rem;
            margin-bottom: 16px;
        }
        .feature-card h4 {
            font-size: 1.05rem;
            margin-bottom: 8px;
            color: var(--primary);
        }
        .feature-card p {
            font-size: 0.95rem;
            color: var(--text-light);
            line-height: 1.55;
        }

        /* ── Specs Table ── */
        .specs { background: var(--bg); }
        .specs-table-wrap {
            overflow-x: auto;
            border-radius: var(--radius);
            border: 1px solid var(--border);
            box-shadow: var(--shadow);
        }
        table.specs-table {
            width: 100%;
            border-collapse: collapse;
            min-width: 700px;
        }
        .specs-table thead {
            background: var(--primary);
            color: #fff;
        }
        .specs-table th {
            padding: 14px 16px;
            text-align: left;
            font-weight: 600;
            font-size: 0.9rem;
            white-space: nowrap;
        }
        .specs-table td {
            padding: 14px 16px;
            border-bottom: 1px solid var(--border);
            font-size: 0.95rem;
        }
        .specs-table tbody tr:hover { background: var(--bg-light); }
        .specs-table tbody tr:last-child td { border-bottom: none; }
        .spec-highlight {
            font-weight: 700;
            color: var(--accent);
        }
        .spec-note {
            margin-top: 16px;
            font-size: 0.85rem;
            color: var(--text-light);
            font-style: italic;
        }

        /* ── How It Works ── */
        .how-it-works { background: var(--bg-light); }
        .hiw-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
            gap: 24px;
        }
        .hiw-card {
            background: var(--bg);
            border-radius: var(--radius);
            padding: 32px 24px;
            text-align: center;
            box-shadow: var(--shadow);
            border: 1px solid var(--border);
        }
        .hiw-num {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            width: 44px;
            height: 44px;
            border-radius: 50%;
            background: var(--primary);
            color: #fff;
            font-weight: 800;
            font-size: 1.2rem;
            margin-bottom: 14px;
        }
        .hiw-card h4 { margin-bottom: 8px; }
        .hiw-card p { font-size: 0.95rem; color: var(--text-light); }

        /* ── Applications ── */
        .applications { background: var(--bg); }
        .app-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
            gap: 24px;
        }
        .app-card {
            background: var(--bg-light);
            border-radius: var(--radius);
            padding: 28px;
            border: 1px solid var(--border);
            transition: box-shadow .2s;
        }
        .app-card:hover { box-shadow: var(--shadow-lg); }
        .app-card h4 {
            font-size: 1.1rem;
            color: var(--primary);
            margin-bottom: 8px;
        }
        .app-card p {
            font-size: 0.95rem;
            color: var(--text-light);
            line-height: 1.55;
        }
        .app-card .app-tag {
            display: inline-block;
            background: #e8f0fe;
            color: var(--primary-light);
            font-size: 0.78rem;
            padding: 3px 10px;
            border-radius: 12px;
            margin-top: 10px;
            font-weight: 600;
        }

        /* ── Cert / Trust ── */
        .cert { background: var(--bg-dark); color: var(--text-inverse); }
        .cert h2 { color: #fff; }
        .cert-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
            gap: 24px;
            margin-top: 32px;
        }
        .cert-card {
            background: rgba(255,255,255,0.06);
            border: 1px solid rgba(255,255,255,0.12);
            border-radius: var(--radius);
            padding: 28px;
            text-align: center;
        }
        .cert-card .cert-badge {
            font-size: 2.5rem;
            margin-bottom: 12px;
        }
        .cert-card h4 { color: #ffb347; margin-bottom: 8px; }
        .cert-card p { font-size: 0.9rem; opacity: 0.8; }

        /* ── Comparison Section ── */
        .comparison { background: var(--bg-light); }
        .comparison-table-wrap {
            overflow-x: auto;
            border-radius: var(--radius);
            border: 1px solid var(--border);
            box-shadow: var(--shadow);
        }
        table.comparison-table {
            width: 100%;
            border-collapse: collapse;
            min-width: 600px;
        }
        .comparison-table th {
            background: #f0f2f5;
            padding: 12px 16px;
            text-align: left;
            font-weight: 700;
            font-size: 0.9rem;
            border-bottom: 2px solid var(--border);
        }
        .comparison-table td {
            padding: 12px 16px;
            border-bottom: 1px solid var(--border);
            font-size: 0.95rem;
        }
        .comparison-table tbody tr:hover { background: #fff; }
        .tick { color: #2e8b57; font-weight: 700; }
        .cross { color: #c0392b; }

        /* ── CTA Banner ── */
        .cta-banner {
            background: linear-gradient(135deg, var(--accent) 0%, #d46200 100%);
            color: #fff;
            text-align: center;
            padding: 56px 20px;
        }
        .cta-banner h2 {
            color: #fff;
            font-size: 2rem;
            margin-bottom: 12px;
        }
        .cta-banner p {
            font-size: 1.1rem;
            opacity: 0.95;
            margin-bottom: 28px;
            max-width: 560px;
            margin-left: auto;
            margin-right: auto;
        }
        .btn-white {
            display: inline-block;
            padding: 14px 36px;
            border-radius: 6px;
            font-weight: 700;
            font-size: 1rem;
            text-decoration: none;
            background: #fff;
            color: var(--accent);
            transition: all .2s;
        }
        .btn-white:hover {
            box-shadow: 0 4px 20px rgba(0,0,0,0.2);
            transform: translateY(-1px);
        }

        /* ── FAQ ── */
        .faq { background: var(--bg); }
        .faq-list { max-width: 800px; }
        .faq-item {
            border-bottom: 1px solid var(--border);
            padding: 20px 0;
        }
        .faq-item:first-child { border-top: 1px solid var(--border); }
        .faq-q {
            font-weight: 700;
            font-size: 1.05rem;
            margin-bottom: 8px;
            color: var(--primary);
            cursor: default;
        }
        .faq-a {
            color: var(--text-light);
            font-size: 0.95rem;
            line-height: 1.65;
        }

        /* ── Related Links ── */
        .related { background: var(--bg-light); }
        .related-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 20px;
        }
        .related-card {
            background: var(--bg);
            border: 1px solid var(--border);
            border-radius: var(--radius);
            padding: 24px;
            text-decoration: none;
            color: var(--text);
            transition: all .2s;
            display: block;
        }
        .related-card:hover {
            box-shadow: var(--shadow-lg);
            border-color: var(--primary-light);
        }
        .related-card h4 {
            color: var(--primary-light);
            margin-bottom: 6px;
            font-size: 1rem;
        }
        .related-card p {
            font-size: 0.9rem;
            color: var(--text-light);
            line-height: 1.5;
        }
        .related-card .arrow {
            display: inline-block;
            margin-top: 10px;
            font-weight: 700;
            color: var(--accent);
            font-size: 0.9rem;
        }

        /* ── Footer ── */
        .site-footer {
            background: var(--bg-dark);
            color: rgba(255,255,255,0.7);
            padding: 40px 20px 28px;
            font-size: 0.9rem;
        }
        .footer-inner {
            max-width: var(--max-width);
            margin: 0 auto;
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 32px;
        }
        .footer-col h5 {
            color: #fff;
            font-size: 0.95rem;
            margin-bottom: 14px;
        }
        .footer-col ul { list-style: none; }
        .footer-col ul li { margin-bottom: 8px; }
        .footer-col a {
            color: rgba(255,255,255,0.6);
            text-decoration: none;
            font-size: 0.9rem;
        }
        .footer-col a:hover { color: #fff; }
        .footer-bottom {
            max-width: var(--max-width);
            margin: 28px auto 0;
            padding-top: 20px;
            border-top: 1px solid rgba(255,255,255,0.1);
            text-align: center;
            font-size: 0.85rem;
            opacity: 0.7;
        }

        /* ── Responsive ── */
        @media (max-width: 768px) {
            .hero h1 { font-size: 1.75rem; }
            .hero-stats { gap: 24px; }
            .hero-stat-num { font-size: 1.5rem; }
            .overview-grid { grid-template-columns: 1fr; gap: 28px; }
            .btn-outline { margin-left: 0; margin-top: 10px; }
            h2 { font-size: 1.5rem; }
            .nav-links { display: none; }
        }

        @media (max-width: 480px) {
            section { padding: 40px 16px; }
            .hero { padding: 40px 16px 36px; }
            .hero h1 { font-size: 1.45rem; }
            .hero-desc { font-size: 1rem; }
            .btn { display: block; width: 100%; text-align: center; }
            .btn-outline { margin-left: 0; margin-top: 10px; }
        }