:root {
  --radius: 0.5rem;
  --background: oklch(0.075 0.015 264);
  --foreground: oklch(0.97 0.012 255);
  --card: oklch(0.12 0.024 263);
  --card-foreground: oklch(0.97 0.012 255);
  --popover: oklch(0.12 0.024 263);
  --popover-foreground: oklch(0.97 0.012 255);
  --primary: oklch(0.65 0.2 253);
  --primary-foreground: oklch(1 0 0);
  --secondary: oklch(0.97 0.01 250);
  --secondary-foreground: oklch(0.11 0.025 263);
  --muted: oklch(0.16 0.025 263);
  --muted-foreground: oklch(0.7 0.025 255);
  --accent: oklch(0.72 0.16 204);
  --accent-foreground: oklch(0.08 0.018 263);
  --destructive: oklch(0.62 0.22 28);
  --destructive-foreground: oklch(1 0 0);
  --border: oklch(0.3 0.035 258 / 0.72);
  --input: oklch(0.22 0.03 258);
  --ring: oklch(0.65 0.2 253);
  --hero-shadow: oklch(0.03 0.015 260 / 0.98);
  --hero-shadow-soft: oklch(0.035 0.02 260 / 0.7);
  --surface-high: oklch(0.15 0.035 260);
  --line-bright: oklch(0.65 0.18 237 / 0.38);
}

* { box-sizing: border-box; border-color: var(--border); }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--background); color: var(--foreground); font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", Arial, sans-serif; letter-spacing: 0; }
a { color: inherit; text-decoration: none; }
button, a { -webkit-tap-highlight-color: transparent; }
.site { min-height: 100vh; overflow: hidden; background: var(--background); }
.shell { width: min(1180px, calc(100% - 48px)); margin-inline: auto; }
.narrow { max-width: 790px; text-align: center; }
.site-header { position: fixed; inset: 0 0 auto; z-index: 50; border-bottom: 1px solid var(--border); background: oklch(0.04 0.012 260 / 0.88); backdrop-filter: blur(18px); }
.header-inner { height: 72px; display: flex; align-items: center; justify-content: space-between; gap: 30px; }
.logo { flex: 0 0 auto; font-size: 23px; font-weight: 650; color: var(--primary); }
.brand b { font-weight: 500; }
.brand-mark { display: inline-grid; place-items: center; width: 28px; height: 28px; margin-right: 1px; border: 3px solid currentColor; border-radius: 50%; line-height: 1; font-size: 18px; transform: rotate(-15deg); }
.desktop-nav { display: flex; align-items: center; gap: 34px; color: var(--muted-foreground); font-size: 14px; }
.desktop-nav a:hover, .footer a:hover, .language-link:hover { color: var(--foreground); }
.header-actions { display: flex; align-items: center; gap: 16px; }
.language-link { display: flex; align-items: center; gap: 7px; font-size: 13px; color: var(--muted-foreground); }
.language-link svg { width: 16px; }
.mobile-menu { display: none; position: relative; }
.mobile-menu summary { cursor: pointer; list-style: none; font-size: 24px; }
.mobile-menu nav { position: absolute; right: 0; top: 42px; width: 220px; display: grid; gap: 4px; padding: 12px; background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); box-shadow: 0 20px 50px oklch(0 0 0 / .4); }
.mobile-menu nav a { padding: 11px 12px; color: var(--muted-foreground); }
.hero { min-height: min(820px, 100svh); display: flex; align-items: center; background-position: center; background-size: cover; border-bottom: 1px solid var(--border); }
.hero-inner { padding-top: 72px; }
.hero-inner > * { max-width: 650px; }
.eyebrow { margin: 0 0 18px; color: var(--accent); font-size: 12px; font-weight: 700; letter-spacing: .16em; text-transform: uppercase; }
h1, h2, h3, p { margin-top: 0; }
h1 { margin-bottom: 22px; font-size: clamp(46px, 6vw, 78px); line-height: 1.08; letter-spacing: 0; }
.hero-copy { max-width: 590px; color: oklch(0.79 0.025 255); font-size: 19px; line-height: 1.85; }
.hero-actions { display: flex; gap: 12px; margin-top: 32px; }
.hero-actions a { min-width: 138px; }
.section { padding: 112px 0; }
.section h2 { font-size: clamp(34px, 4vw, 52px); line-height: 1.18; letter-spacing: 0; }
.section-lead { color: var(--muted-foreground); font-size: 18px; line-height: 1.8; }
.section-lead.left { max-width: 580px; }
.feature-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px; margin-top: 64px; background: var(--border); border: 1px solid var(--border); }
.feature { min-height: 280px; position: relative; padding: 34px 28px; background: var(--background); }
.feature > svg { width: 30px; height: 30px; color: var(--primary); }
.feature > span { position: absolute; right: 24px; top: 26px; color: var(--muted-foreground); font-size: 12px; }
.feature h3 { margin: 70px 0 12px; font-size: 20px; }
.feature p { color: var(--muted-foreground); line-height: 1.7; }
.product-band { background: var(--secondary); color: var(--secondary-foreground); }
.product-band .eyebrow { color: var(--primary); }
.product-band .section-lead { color: oklch(0.42 0.035 260); }
.product-grid { display: grid; grid-template-columns: 1.1fr .9fr; gap: 100px; align-items: center; }
.connection-visual { min-height: 390px; position: relative; display: grid; place-items: center; overflow: hidden; background: var(--background); color: var(--foreground); }
.connection-visual p { position: absolute; bottom: 38px; color: var(--muted-foreground); }
.q-core { z-index: 2; display: grid; place-items: center; width: 116px; height: 116px; border: 3px solid var(--primary); border-radius: 50%; color: var(--primary); font-size: 72px; font-weight: 700; box-shadow: 0 0 50px oklch(0.65 0.2 253 / .45); }
.orbit { position: absolute; border: 1px solid var(--line-bright); border-radius: 50%; animation: pulse-ring 3s ease-in-out infinite; }
.orbit-one { width: 230px; height: 230px; }
.orbit-two { width: 340px; height: 340px; animation-delay: .7s; }
.status-dot { position: absolute; bottom: 46px; margin-left: -92px; width: 8px; height: 8px; border-radius: 50%; background: oklch(0.78 0.18 152); box-shadow: 0 0 14px currentColor; }
.stats { border-bottom: 1px solid var(--border); background: var(--surface-high); }
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); }
.stats-grid div { padding: 38px 22px; border-right: 1px solid var(--border); text-align: center; }
.stats-grid div:last-child { border: 0; }
.stats strong, .stats span { display: block; }
.stats strong { font-size: 23px; }
.stats span { margin-top: 7px; color: var(--muted-foreground); font-size: 13px; }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: 24px; }
.text-link { display: inline-flex; align-items: center; gap: 8px; color: var(--primary); }
.text-link svg { width: 18px; }
.faq-list { margin-top: 38px; border-top: 1px solid var(--border); }
.faq-list details { border-bottom: 1px solid var(--border); }
.faq-list summary { display: flex; align-items: center; justify-content: space-between; gap: 20px; padding: 25px 4px; cursor: pointer; list-style: none; font-size: 18px; font-weight: 600; }
.faq-list summary span { color: var(--primary); font-size: 24px; font-weight: 300; transition: transform .2s ease; }
.faq-list details[open] summary span { transform: rotate(45deg); }
.faq-list details p { max-width: 780px; padding: 0 4px 26px; color: var(--muted-foreground); line-height: 1.75; }
.faq-list.large { margin-top: 0; }
.final-cta { padding: 74px 0; background: var(--primary); color: var(--primary-foreground); }
.final-cta .shell { display: flex; align-items: center; justify-content: space-between; gap: 30px; }
.final-cta .eyebrow { color: var(--primary-foreground); opacity: .75; }
.final-cta h2 { margin: 0; font-size: clamp(30px, 4vw, 46px); }
.final-cta a { background: var(--secondary); color: var(--secondary-foreground); }
.footer { padding: 70px 0 26px; border-top: 1px solid var(--border); background: oklch(0.055 0.012 263); }
.footer-grid { display: grid; grid-template-columns: 2fr repeat(3, 1fr); gap: 50px; }
.footer-grid > div:first-child p { max-width: 420px; margin-top: 22px; color: var(--muted-foreground); line-height: 1.7; }
.footer h2 { font-size: 14px; }
.footer-grid > div:not(:first-child) { display: flex; flex-direction: column; gap: 13px; }
.footer-grid a:not(.logo) { color: var(--muted-foreground); font-size: 14px; }
.footer-bottom { display: flex; justify-content: space-between; margin-top: 54px; padding-top: 24px; border-top: 1px solid var(--border); color: var(--muted-foreground); font-size: 12px; }
.page-hero { padding: 142px 0 82px; border-bottom: 1px solid var(--border); background: radial-gradient(circle at 76% 36%, oklch(0.35 0.14 252 / .24), transparent 30%), var(--background); }
.page-hero h1 { max-width: 850px; margin-bottom: 20px; font-size: clamp(42px, 5vw, 64px); }
.page-hero > .shell > p:last-child { max-width: 760px; color: var(--muted-foreground); font-size: 18px; line-height: 1.75; }
.breadcrumbs { display: flex; align-items: center; gap: 7px; margin-bottom: 58px; color: var(--muted-foreground); font-size: 13px; }
.breadcrumbs svg { width: 14px; }
.download-primary { display: flex; align-items: center; justify-content: space-between; gap: 40px; padding: 46px; border: 1px solid var(--line-bright); background: var(--surface-high); }
.download-primary > div { max-width: 650px; }
.download-primary h2 { font-size: 36px; }
.download-primary p:last-child, .device-card p, .device-card span { color: var(--muted-foreground); line-height: 1.7; }
.os-icon { display: grid; place-items: center; width: 52px; height: 52px; margin-bottom: 32px; background: var(--primary); color: var(--primary-foreground); border-radius: var(--radius); }
.device-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin-top: 22px; }
.device-card { min-height: 245px; padding: 30px; border: 1px solid var(--border); background: var(--card); }
.device-card > svg { width: 30px; height: 30px; margin-bottom: 45px; color: var(--primary); }
.device-card h2 { margin-bottom: 8px; font-size: 24px; }
.device-card span { font-size: 13px; }
.notice { margin-bottom: 26px; padding: 16px 20px; border-left: 3px solid var(--accent); background: var(--muted); color: var(--muted-foreground); line-height: 1.6; }
.pricing-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; align-items: stretch; }
.price-card { position: relative; padding: 38px 30px; border: 1px solid var(--border); background: var(--card); }
.price-card.featured { border-color: var(--primary); transform: translateY(-8px); }
.plan-tag { position: absolute; top: 0; right: 0; padding: 7px 10px; background: var(--primary); color: var(--primary-foreground); font-size: 10px; font-weight: 700; }
.price-card h2 { font-size: 24px; }
.price-card > strong { display: block; margin: 28px 0 6px; font-size: 48px; }
.price-card > p { color: var(--muted-foreground); }
.price-card ul { min-height: 145px; padding: 22px 0 0; border-top: 1px solid var(--border); list-style: none; }
.price-card li { display: flex; gap: 9px; margin: 13px 0; color: var(--muted-foreground); }
.price-card li svg { width: 17px; color: var(--accent); }
.price-card a { width: 100%; }
.content-panel { margin-top: 60px; padding: 44px; border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.content-panel h2 { font-size: 30px; }
.prose-columns { display: grid; grid-template-columns: 1fr 1fr; gap: 44px; color: var(--muted-foreground); line-height: 1.8; }
.reason-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1px; background: var(--border); border: 1px solid var(--border); }
.reason { position: relative; min-height: 240px; padding: 38px; background: var(--background); }
.reason > span { color: var(--primary); font-size: 12px; }
.reason h2 { margin-top: 52px; font-size: 25px; }
.reason p { color: var(--muted-foreground); line-height: 1.7; }
.accent-panel { display: flex; align-items: flex-start; gap: 24px; background: var(--surface-high); }
.accent-panel > svg { flex: 0 0 auto; width: 36px; height: 36px; color: var(--accent); }
.accent-panel h2 { margin-bottom: 10px; }
.accent-panel p { margin: 0; color: var(--muted-foreground); line-height: 1.75; }
.legal-copy { max-width: 880px; }
.legal-copy > section { display: grid; grid-template-columns: 52px 1fr; gap: 22px; padding: 34px 0; border-bottom: 1px solid var(--border); }
.legal-copy > section > span { color: var(--primary); font-size: 12px; font-weight: 700; }
.legal-copy h2 { margin-bottom: 12px; font-size: 24px; }
.legal-copy p { color: var(--muted-foreground); line-height: 1.85; }
@keyframes pulse-ring { 0%,100% { transform: scale(.96); opacity: .45; } 50% { transform: scale(1.04); opacity: 1; } }
@media (prefers-reduced-motion: reduce) { * { scroll-behavior: auto !important; animation: none !important; transition: none !important; } }
@media (max-width: 900px) {
  .desktop-nav, .header-actions { display: none; }
  .mobile-menu { display: block; }
  .hero { min-height: 720px; background-position: 64% center; }
  .hero-inner { align-self: flex-end; padding-bottom: 72px; }
  .feature-grid, .pricing-grid { grid-template-columns: 1fr 1fr; }
  .product-grid { grid-template-columns: 1fr; gap: 56px; }
  .footer-grid { grid-template-columns: 2fr 1fr 1fr; }
  .footer-grid > div:last-child { grid-column: 2; }
}
@media (max-width: 640px) {
  .shell { width: min(100% - 32px, 1180px); }
  .header-inner { height: 64px; }
  .logo { font-size: 20px; }
  .brand-mark { width: 24px; height: 24px; font-size: 15px; }
  .hero { min-height: 690px; background-position: 67% center; }
  .hero-inner { padding-top: 150px; }
  h1 { font-size: 44px; }
  .hero-copy { font-size: 16px; }
  .hero-actions { flex-direction: column; align-items: stretch; width: 100%; }
  .section { padding: 78px 0; }
  .section h2 { font-size: 34px; }
  .feature-grid, .device-grid, .pricing-grid, .reason-grid, .stats-grid, .footer-grid, .prose-columns { grid-template-columns: 1fr; }
  .feature { min-height: 230px; }
  .feature h3 { margin-top: 44px; }
  .stats-grid div { border-right: 0; border-bottom: 1px solid var(--border); }
  .section-heading, .final-cta .shell, .download-primary { align-items: flex-start; flex-direction: column; }
  .connection-visual { min-height: 330px; }
  .footer-grid > div:last-child { grid-column: auto; }
  .footer-bottom { flex-direction: column; gap: 8px; }
  .page-hero { padding: 112px 0 62px; }
  .breadcrumbs { margin-bottom: 40px; }
  .download-primary, .content-panel { padding: 28px; }
  .price-card.featured { transform: none; }
  .legal-copy > section { grid-template-columns: 1fr; gap: 10px; }
}
.btn { display:inline-flex; align-items:center; justify-content:center; min-height:44px; padding:0 24px; border-radius:var(--radius); background:var(--primary); color:var(--primary-foreground); font-size:14px; font-weight:600; }
.btn.outline { border:1px solid var(--border); background:var(--background); color:var(--foreground); }