/* ============ CSS Variables ============ */
        :root {
            --bg-primary: #0B1220;
            --bg-secondary: #111C33;
            --bg-card: rgba(255, 255, 255, 0.03);
            --bg-card-hover: rgba(255, 255, 255, 0.06);
            --border-subtle: rgba(255, 255, 255, 0.07);
            --border-strong: rgba(255, 255, 255, 0.14);
            --accent-primary: #00E5CC;
            --accent-primary-dim: rgba(0, 229, 204, 0.14);
            --accent-secondary: #6C5CE7;
            --accent-secondary-dim: rgba(108, 92, 231, 0.16);
            --accent-gold: #FFB300;
            --accent-gold-dim: rgba(255, 179, 0, 0.14);
            --accent-danger: #FF5C7A;
            --accent-danger-dim: rgba(255, 92, 122, 0.14);
            --text-primary: #FFFFFF;
            --text-secondary: rgba(255, 255, 255, 0.72);
            --text-tertiary: rgba(255, 255, 255, 0.45);
            --text-on-accent: #0B1220;
            --font-sans: 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
            --font-mono: 'JetBrains Mono', 'SF Mono', 'Fira Code', 'Consolas', monospace;
            --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.28);
            --shadow-glow: 0 0 42px rgba(0, 229, 204, 0.10);
            --shadow-glow-strong: 0 0 72px rgba(0, 229, 204, 0.18);
            --radius-sm: 10px;
            --radius-md: 16px;
            --radius-lg: 24px;
            --radius-xl: 32px;
            --transition-fast: 180ms ease;
            --transition-medium: 320ms ease;
            --transition-slow: 520ms cubic-bezier(0.22, 1, 0.36, 1);
            --section-pad: 96px 0;
            --shell-max: 1200px;
            --shell-pad: 0 40px;
        }

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

        html {
            scroll-behavior: smooth;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
            background: var(--bg-primary);
        }

        body {
            font-family: var(--font-sans);
            font-size: 16px;
            line-height: 1.7;
            color: var(--text-secondary);
            background: var(--bg-primary);
            overflow-x: hidden;
            min-height: 100vh;
        }

        img { max-width: 100%; height: auto; display: block; }
        a { color: var(--accent-primary); text-decoration: none; transition: color var(--transition-fast); }
        a:hover { color: #33F5E0; }
        h1, h2, h3, h4, h5, h6 { color: var(--text-primary); font-weight: 700; line-height: 1.25; letter-spacing: -0.02em; }
        h1 { font-size: clamp(2.6rem, 6vw, 4.8rem); font-weight: 800; letter-spacing: -0.04em; }
        h2 { font-size: clamp(1.8rem, 3.5vw, 2.8rem); letter-spacing: -0.03em; }
        h3 { font-size: clamp(1.25rem, 2vw, 1.6rem); letter-spacing: -0.02em; }
        ul, ol { list-style: none; }
        .section-shell { max-width: var(--shell-max); margin: 0 auto; padding: var(--shell-pad); }

        /* ============ Header ============ */
        .site-header {
            position: sticky; top: 0; z-index: 1000;
            background: rgba(11, 18, 32, 0.82);
            backdrop-filter: blur(22px);
            -webkit-backdrop-filter: blur(22px);
            border-bottom: 1px solid var(--border-subtle);
            transition: background var(--transition-medium);
        }
        .site-header.scrolled { background: rgba(11, 18, 32, 0.95); border-bottom-color: var(--border-strong); }
        .header-inner { display: flex; align-items: center; justify-content: space-between; height: 72px; gap: 24px; }
        .brand { display: flex; align-items: center; gap: 10px; font-size: 1.35rem; font-weight: 800; color: var(--text-primary); letter-spacing: -0.02em; flex-shrink: 0; }
        .brand svg { width: 38px; height: 38px; border-radius: var(--radius-sm); }
        .brand:hover { color: var(--accent-primary); }
        .nav-links { display: flex; align-items: center; gap: 4px; flex-wrap: wrap; justify-content: center; }
        .nav-links a { padding: 8px 14px; border-radius: 8px; font-size: 0.88rem; font-weight: 500; color: var(--text-tertiary); transition: all var(--transition-fast); white-space: nowrap; }
        .nav-links a:hover { color: var(--text-primary); background: var(--bg-card-hover); }
        .nav-links a.active { color: var(--accent-primary); background: var(--accent-primary-dim); font-weight: 600; }
        .header-action { padding: 9px 20px; border-radius: 10px; font-weight: 600; font-size: 0.88rem; background: var(--accent-primary); color: var(--text-on-accent) !important; flex-shrink: 0; transition: all var(--transition-fast); border: none; cursor: pointer; }
        .header-action:hover { background: #33F5E0; transform: translateY(-1px); box-shadow: 0 4px 20px rgba(0,229,204,0.3); }
        .nav-toggle { display: none; background: none; border: 1px solid var(--border-strong); border-radius: 8px; padding: 8px 12px; cursor: pointer; color: var(--text-primary); font-size: 1.2rem; line-height: 1; }

        /* ============ Hero ============ */
        .features-hero {
            padding: 100px 0 80px;
            background:
                radial-gradient(ellipse 50% 45% at 20% 10%, rgba(0,229,204,0.08) 0%, transparent 70%),
                radial-gradient(ellipse 40% 40% at 80% 30%, rgba(108,92,231,0.06) 0%, transparent 60%),
                var(--bg-primary);
            border-bottom: 1px solid var(--border-subtle);
            position: relative;
            overflow: hidden;
        }
        .features-hero::before {
            content: ''; position: absolute; inset: 0;
            background-image: linear-gradient(rgba(255,255,255,0.015) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,0.015) 1px, transparent 1px);
            background-size: 72px 72px; pointer-events: none;
            mask-image: radial-gradient(ellipse 70% 60% at 50% 40%, black 30%, transparent 70%);
            -webkit-mask-image: radial-gradient(ellipse 70% 60% at 50% 40%, black 30%, transparent 70%);
        }
        .features-hero-inner {
            position: relative; z-index: 1;
            display: grid;
            grid-template-columns: 1.1fr 0.9fr;
            gap: 48px;
            align-items: center;
        }
        .features-hero-copy .eyebrow {
            font-family: var(--font-mono);
            font-size: 0.78rem;
            letter-spacing: 0.18em;
            text-transform: uppercase;
            color: var(--accent-primary);
            margin-bottom: 16px;
            display: flex; align-items: center; gap: 10px;
        }
        .features-hero-copy .eyebrow::before { content:''; width:32px; height:2px; background:var(--accent-primary); border-radius:2px; }
        .features-hero-copy h1 {
            margin-bottom: 20px;
            background: linear-gradient(135deg, #FFFFFF 20%, #B0E8E0 60%, #00E5CC 100%);
            -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; color: transparent;
        }
        .features-hero-copy>p:not(.eyebrow) {
            font-size: 1.12rem; line-height: 1.85; max-width: 540px; margin-bottom: 36px; color: var(--text-secondary);
        }
        .hero-badge-group {
            display: flex; flex-wrap: wrap; gap: 10px;
        }
        .badge {
            padding: 8px 16px; border-radius: 20px; font-size: 0.85rem; font-weight: 600;
            background: var(--bg-card); border: 1px solid var(--border-subtle); color: var(--text-secondary);
        }
        .badge.highlight { background: var(--accent-primary-dim); border-color: rgba(0,229,204,0.3); color: var(--accent-primary); }
        .hero-visual {
            display: flex; justify-content: center; align-items: center;
            min-height: 300px;
            background: var(--bg-card);
            border-radius: var(--radius-xl);
            border: 1px solid var(--border-subtle);
            box-shadow: var(--shadow-card);
            backdrop-filter: blur(12px);
            padding: 40px;
            position: relative;
        }
        .feature-icon-grid {
            display: grid; grid-template-columns: repeat(3,1fr); gap: 20px;
            text-align: center;
        }
        .feature-icon-item {
            padding: 20px 12px; background: rgba(0,0,0,0.3); border-radius: var(--radius-md);
            border: 1px solid var(--border-subtle); transition: all var(--transition-medium);
        }
        .feature-icon-item:hover { border-color: var(--accent-primary); transform: translateY(-4px); }
        .feature-icon-item .icon { font-size: 2.2rem; margin-bottom: 10px; }
        .feature-icon-item span { font-size: 0.85rem; color: var(--text-tertiary); }

        /* ============ Feature Grid (Core) ============ */
        .core-features {
            padding: var(--section-pad);
            background: var(--bg-primary);
        }
        .section-heading {
            text-align: center; margin-bottom: 56px;
        }
        .section-heading .eyebrow {
            font-family: var(--font-mono); font-size: 0.78rem; letter-spacing: 0.18em; text-transform: uppercase; color: var(--accent-gold); margin-bottom: 10px;
        }
        .section-heading h2 { margin-bottom: 14px; }
        .section-heading p { max-width: 620px; margin: 0 auto; color: var(--text-secondary); }
        .feature-grid {
            display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px;
        }
        .feature-card {
            padding: 32px 28px; background: var(--bg-card); border-radius: var(--radius-lg);
            border: 1px solid var(--border-subtle); transition: all var(--transition-medium);
            position: relative; overflow: hidden;
        }
        .feature-card::after {
            content:''; position:absolute; top:0; left:0; right:0; height:2px;
            background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
            transform: scaleX(0); transform-origin: left; transition: transform var(--transition-medium);
        }
        .feature-card:hover::after { transform: scaleX(1); }
        .feature-card:hover { border-color: var(--border-strong); background: var(--bg-card-hover); transform: translateY(-6px); }
        .feature-card .icon {
            width: 52px; height: 52px; border-radius: 14px; display: flex; align-items: center; justify-content: center;
            font-size: 1.8rem; margin-bottom: 18px; background: var(--accent-primary-dim);
        }
        .feature-card h3 { font-size: 1.3rem; margin-bottom: 10px; }
        .feature-card p { font-size: 0.94rem; color: var(--text-tertiary); line-height: 1.7; }

        /* ============ Tech Deep Dive ============ */
        .tech-deep {
            padding: var(--section-pad);
            background: var(--bg-secondary);
            border-top: 1px solid var(--border-subtle);
            border-bottom: 1px solid var(--border-subtle);
            position: relative; overflow: hidden;
        }
        .tech-deep::before {
            content:''; position:absolute; top:-30%; left:-10%; width:500px; height:500px;
            background: radial-gradient(circle, rgba(0,229,204,0.05) 0%, transparent 70%);
            pointer-events:none;
        }
        .tech-row {
            display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center;
            margin-bottom: 56px; position: relative; z-index:1;
        }
        .tech-row:last-child { margin-bottom: 0; }
        .tech-row.reverse { direction: rtl; }
        .tech-row.reverse > * { direction: ltr; }
        .tech-copy .eyebrow {
            font-family: var(--font-mono); font-size: 0.78rem; letter-spacing: 0.18em; text-transform: uppercase; color: var(--accent-primary); margin-bottom: 10px;
        }
        .tech-copy h3 { font-size: clamp(1.5rem, 2.5vw, 2rem); margin-bottom: 16px; }
        .tech-copy p { color: var(--text-secondary); max-width: 480px; }
        .tech-visual {
            background: var(--bg-card); border-radius: var(--radius-xl); padding: 40px;
            border: 1px solid var(--border-subtle); box-shadow: var(--shadow-card);
            text-align: center;
        }
        .tech-visual .visual-number {
            font-family: var(--font-mono); font-size: 3.2rem; font-weight: 800; color: var(--accent-primary);
            letter-spacing: -0.05em; text-shadow: 0 0 30px rgba(0,229,204,0.3);
        }
        .tech-visual .visual-label { color: var(--text-tertiary); margin-top: 8px; font-size: 0.9rem; }

        /* ============ Performance Stats ============ */
        .performance-stats {
            padding: 72px 0; background: var(--bg-primary); border-bottom: 1px solid var(--border-subtle);
        }
        .stats-grid {
            display: grid; grid-template-columns: repeat(4,1fr); gap: 20px; text-align: center;
        }
        .stat-item {
            padding: 32px 20px; background: var(--bg-card); border-radius: var(--radius-md);
            border: 1px solid var(--border-subtle); transition: all var(--transition-medium);
        }
        .stat-item:hover { border-color: var(--accent-primary); background: var(--bg-card-hover); transform: translateY(-4px); }
        .stat-value { font-family: var(--font-mono); font-size: 2.8rem; font-weight: 800; color: var(--text-primary); letter-spacing: -0.03em; }
        .stat-label { font-size: 0.9rem; color: var(--text-tertiary); margin-top: 6px; }

        /* ============ Compatibility ============ */
        .compatibility {
            padding: var(--section-pad); background: var(--bg-secondary);
            border-top: 1px solid var(--border-subtle); border-bottom: 1px solid var(--border-subtle);
        }
        .compat-grid {
            display: grid; grid-template-columns: repeat(5, 1fr); gap: 16px;
        }
        .compat-item {
            padding: 24px 12px; background: var(--bg-card); border-radius: var(--radius-md);
            border: 1px solid var(--border-subtle); text-align: center; transition: all var(--transition-medium);
        }
        .compat-item:hover { border-color: var(--accent-secondary); background: var(--accent-secondary-dim); transform: translateY(-4px); }
        .compat-icon { font-size: 2rem; margin-bottom: 10px; }
        .compat-item span { font-size: 0.9rem; color: var(--text-secondary); font-weight: 600; }

        /* ============ Scenario ============ */
        .scenario-section {
            padding: var(--section-pad); background: var(--bg-primary);
        }
        .scenario-grid {
            display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px;
        }
        .scenario-card {
            padding: 28px 22px; background: var(--bg-card); border-radius: var(--radius-md);
            border: 1px solid var(--border-subtle); transition: all var(--transition-medium);
        }
        .scenario-card:hover { border-color: var(--accent-gold); background: var(--bg-card-hover); transform: translateY(-4px); }
        .scenario-icon { font-size: 2.2rem; margin-bottom: 12px; }
        .scenario-card h4 { font-size: 1.1rem; margin-bottom: 8px; }
        .scenario-card p { font-size: 0.88rem; color: var(--text-tertiary); }

        /* ============ FAQ ============ */
        .faq-section {
            padding: var(--section-pad); background: var(--bg-secondary);
            border-top: 1px solid var(--border-subtle); border-bottom: 1px solid var(--border-subtle);
        }
        .faq-list {
            max-width: 800px; margin: 0 auto;
        }
        .faq-item {
            padding: 24px 0; border-bottom: 1px solid var(--border-subtle);
        }
        .faq-item:last-child { border-bottom: none; }
        .faq-question {
            font-size: 1.15rem; font-weight: 600; color: var(--text-primary);
            margin-bottom: 10px; cursor: pointer; display: flex; justify-content: space-between; align-items: center;
        }
        .faq-question::after { content: '+'; font-size: 1.6rem; color: var(--accent-primary); transition: transform var(--transition-fast); }
        .faq-question.active::after { transform: rotate(45deg); }
        .faq-answer { font-size: 0.95rem; color: var(--text-secondary); max-height: 0; overflow: hidden; transition: max-height 0.4s ease; }

        /* ============ CTA ============ */
        .cta-section {
            padding: 80px 0; background: var(--bg-primary);
            text-align: center;
        }
        .cta-section h2 { margin-bottom: 16px; }
        .cta-section p { color: var(--text-secondary); max-width: 560px; margin: 0 auto 32px; }
        .cta-actions { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
        .primary-button {
            display: inline-flex; align-items: center; gap: 8px; padding: 14px 32px; border-radius: 12px;
            font-weight: 700; font-size: 1rem; background: var(--accent-primary); color: var(--text-on-accent);
            transition: all var(--transition-medium); border: none; cursor: pointer; letter-spacing: 0.01em;
        }
        .primary-button:hover { background: #33F5E0; transform: translateY(-2px); box-shadow: 0 8px 32px rgba(0,229,204,0.35); color: var(--text-on-accent); }
        .outline-button {
            display: inline-flex; align-items: center; gap: 8px; padding: 14px 28px; border-radius: 12px;
            font-weight: 600; font-size: 1rem; background: transparent; color: var(--text-primary);
            border: 1px solid var(--border-strong); transition: all var(--transition-medium); cursor: pointer;
        }
        .outline-button:hover { border-color: var(--accent-primary); color: var(--accent-primary); background: var(--accent-primary-dim); }

        /* ============ Footer ============ */
        .site-footer { padding: 40px 0; background: var(--bg-secondary); border-top: 1px solid var(--border-subtle); }
        .footer-inner { display: flex; align-items: center; justify-content: space-between; gap: 24px; flex-wrap: wrap; }
        .footer-inner p { font-size: 0.85rem; color: var(--text-tertiary); }

        /* ============ Reveal Animation ============ */
        .reveal { opacity: 0; transform: translateY(24px); transition: opacity 0.7s cubic-bezier(0.22, 1, 0.36, 1), transform 0.7s cubic-bezier(0.22, 1, 0.36, 1); }
        .reveal.visible { opacity: 1; transform: translateY(0); }

        /* ============ Responsive ============ */
        @media (max-width: 1024px) {
            .features-hero-inner { grid-template-columns: 1fr; gap: 36px; }
            .feature-grid { grid-template-columns: 1fr 1fr; }
            .tech-row { grid-template-columns: 1fr; gap: 28px; }
            .tech-row.reverse { direction: ltr; }
            .stats-grid { grid-template-columns: 1fr 1fr; }
            .compat-grid { grid-template-columns: repeat(3,1fr); }
            .scenario-grid { grid-template-columns: 1fr 1fr; }
        }
        @media (max-width: 768px) {
            :root { --shell-pad: 0 20px; --section-pad: 64px 0; }
            .nav-links { display: none; position: absolute; top: 72px; left: 0; right: 0; background: rgba(11,18,32,0.96); backdrop-filter: blur(22px); flex-direction: column; padding: 16px 20px; border-bottom: 1px solid var(--border-subtle); }
            .nav-links.open { display: flex; }
            .nav-toggle { display: block; }
            .header-action { display: none; }
            .feature-grid { grid-template-columns: 1fr; }
            .stats-grid { grid-template-columns: 1fr; }
            .compat-grid { grid-template-columns: repeat(2,1fr); }
            .scenario-grid { grid-template-columns: 1fr; }
        }
        @media (max-width: 480px) {
            .compat-grid { grid-template-columns: 1fr; }
        }