:root {
  --ink: #0b0d10;
  --ink-soft: #30343b;
  --paper: #ffffff;
  --mist: #f3f5f7;
  --line: #dfe3e8;
  --blue: #2563eb;
  --blue-dark: #1747b8;
  --green: #19a463;
  --coral: #ef5444;
  --muted: #68707c;
  --content: 1180px;
  --header: 68px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: calc(var(--header) + 16px); }
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: "Segoe UI", "Microsoft YaHei UI", "Microsoft YaHei", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.65;
  letter-spacing: 0;
  -webkit-font-smoothing: antialiased;
}
img { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button, input, summary { font: inherit; letter-spacing: 0; }
button { color: inherit; }
h1, h2, h3, p { margin-top: 0; }
h1, h2, h3 { line-height: 1.15; letter-spacing: 0; }
h2 { margin-bottom: 22px; font-size: clamp(2rem, 4.4vw, 4rem); font-weight: 760; }
h3 { margin-bottom: 10px; font-size: 1.25rem; }

.skip-link { position: fixed; left: 16px; top: -60px; z-index: 1000; padding: 10px 16px; background: #fff; border: 2px solid var(--ink); }
.skip-link:focus { top: 12px; }
.site-header { position: fixed; inset: 0 0 auto; z-index: 100; height: var(--header); color: #fff; border-bottom: 1px solid rgba(255,255,255,.2); transition: background-color .2s, color .2s, border-color .2s; }
.site-header.scrolled { color: var(--ink); background: rgba(255,255,255,.96); border-color: var(--line); box-shadow: 0 8px 30px rgba(11,13,16,.06); }
.header-inner { width: min(calc(100% - 40px), var(--content)); height: 100%; margin: auto; display: flex; align-items: center; justify-content: space-between; gap: 28px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-size: 1.08rem; font-weight: 750; }
.brand img { width: 34px; height: 34px; }
.main-nav { display: flex; align-items: center; gap: 30px; font-size: .92rem; font-weight: 600; }
.main-nav a { position: relative; padding: 8px 0; }
.main-nav a:not(.nav-github)::after { content: ""; position: absolute; left: 0; right: 100%; bottom: 3px; height: 2px; background: currentColor; transition: right .2s; }
.main-nav a:hover::after { right: 0; }
.nav-github { padding: 8px 13px !important; border: 1px solid currentColor; border-radius: 6px; }
.menu-toggle { display: none; width: 42px; height: 42px; padding: 10px; border: 0; background: transparent; }
.menu-toggle span { display: block; height: 2px; margin: 5px 0; background: currentColor; transition: transform .2s, opacity .2s; }

.hero { position: relative; min-height: min(880px, 94vh); display: flex; align-items: center; color: #fff; background: #252a31 url("images/hero-annotation.png") center center / cover no-repeat; overflow: hidden; }
.hero-scrim { position: absolute; inset: 0; background: rgba(11,13,16,.7); }
.hero-content { position: relative; z-index: 2; width: min(calc(100% - 40px), var(--content)); margin: auto; padding: calc(var(--header) + 58px) 0 92px; }
.release-pill { width: max-content; margin-bottom: 24px; padding: 7px 12px; border: 1px solid rgba(255,255,255,.45); border-radius: 999px; color: rgba(255,255,255,.88); font-size: .82rem; font-weight: 650; }
.release-pill span { display: inline-block; width: 8px; height: 8px; margin-right: 7px; border-radius: 50%; background: #35d58a; box-shadow: 0 0 0 4px rgba(53,213,138,.17); }
.hero h1 { margin-bottom: 6px; font-size: clamp(4rem, 10vw, 8.5rem); font-weight: 820; }
.hero-lead { margin-bottom: 20px; font-size: clamp(1.5rem, 3vw, 2.75rem); font-weight: 680; }
.hero-copy { max-width: 680px; margin-bottom: 34px; color: rgba(255,255,255,.78); font-size: 1.08rem; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }
.button { min-height: 48px; display: inline-flex; align-items: center; justify-content: center; gap: 9px; padding: 11px 20px; border: 1px solid transparent; border-radius: 6px; font-weight: 700; transition: transform .2s, background-color .2s, border-color .2s; }
.button:hover { transform: translateY(-2px); }
.button-primary { color: #fff; background: var(--blue); }
.button-primary:hover { background: var(--blue-dark); }
.button-secondary { color: var(--ink); border-color: var(--ink); background: #fff; }
.button-secondary:hover { color: #fff; background: var(--ink); }
.button-ghost { color: #fff; border-color: rgba(255,255,255,.45); background: rgba(11,13,16,.22); }
.button-ghost:hover { border-color: #fff; background: rgba(11,13,16,.45); }
.button.large { min-height: 56px; padding: 14px 24px; }
.button.full { width: 100%; }
.button-icon { font-size: 1.35rem; line-height: 1; }
.hero-meta { display: flex; flex-wrap: wrap; gap: 0; margin-top: 30px; color: rgba(255,255,255,.65); font-size: .84rem; }
.hero-meta span { display: flex; align-items: center; }
.hero-meta span + span::before { content: ""; width: 3px; height: 3px; margin: 0 12px; border-radius: 50%; background: currentColor; }
.hero-next { position: absolute; z-index: 2; left: 50%; bottom: 22px; width: 38px; height: 38px; transform: translateX(-50%); border: 1px solid rgba(255,255,255,.35); border-radius: 50%; }
.hero-next span { position: absolute; left: 12px; top: 10px; width: 12px; height: 12px; border-right: 2px solid #fff; border-bottom: 2px solid #fff; transform: rotate(45deg); }

.section { padding: 112px 0; }
.section-inner { width: min(calc(100% - 40px), var(--content)); margin: auto; }
.section-heading { max-width: 790px; margin-bottom: 64px; }
.section-heading > p:last-child { max-width: 680px; color: var(--muted); font-size: 1.05rem; }
.section-heading.left { margin-bottom: 32px; }
.eyebrow { margin-bottom: 16px; color: var(--blue); font-size: .79rem; font-weight: 800; text-transform: uppercase; }
.eyebrow.coral { color: var(--coral); }
.eyebrow.green { color: var(--green); }
.eyebrow.blue { color: #6da0ff; }
.workflow-steps { border-top: 1px solid var(--line); }
.workflow-step { min-height: 136px; display: grid; grid-template-columns: 110px minmax(0, 1fr); align-items: center; gap: 28px; border-bottom: 1px solid var(--line); }
.step-number { color: var(--coral); font-size: 1.1rem; font-weight: 800; }
.workflow-step h3 { margin: 0 0 8px; font-size: clamp(1.4rem, 3vw, 2rem); }
.workflow-step p { max-width: 680px; margin: 0; color: var(--muted); }

.showcase { padding: 112px 0; }
.showcase-light { background: #fff; }
.showcase-paper { background: #eef4f1; }
.showcase-dark { color: #fff; background: #111418; }
.showcase-inner { width: min(calc(100% - 40px), 1320px); margin: auto; display: grid; grid-template-columns: minmax(280px, .72fr) minmax(0, 1.28fr); align-items: center; gap: clamp(48px, 7vw, 110px); }
.showcase-inner.reverse { grid-template-columns: minmax(280px, .7fr) minmax(0, 1.3fr); }
.showcase-inner.reverse .showcase-copy { order: 2; }
.showcase-inner.reverse .product-shot { order: 1; }
.showcase-copy h2 { max-width: 520px; font-size: clamp(2.2rem, 4.3vw, 4.5rem); }
.showcase-copy > p:not(.eyebrow):not(.privacy-inline) { max-width: 560px; color: var(--muted); font-size: 1.05rem; }
.showcase-dark .showcase-copy > p:not(.eyebrow) { color: #aeb6c2; }
.feature-list { padding: 0; margin: 28px 0 0; list-style: none; }
.feature-list li { position: relative; padding: 12px 0 12px 24px; border-bottom: 1px solid var(--line); }
.feature-list li::before { content: ""; position: absolute; left: 0; top: 21px; width: 8px; height: 8px; background: var(--coral); }
.product-shot { margin: 0; }
.product-shot img { width: 100%; max-height: 650px; object-fit: contain; border-radius: 6px; box-shadow: 0 24px 70px rgba(11,13,16,.16); }
.showcase-dark .product-shot img { box-shadow: 0 30px 80px rgba(0,0,0,.42); }
.product-shot figcaption { margin-top: 12px; color: var(--muted); font-size: .82rem; }
.showcase-dark .product-shot figcaption { color: #828b98; }
.signal-row { display: flex; gap: 36px; margin-top: 34px; color: #aeb6c2; }
.signal-row span { display: flex; flex-direction: column; }
.signal-row strong { color: #fff; font-size: 1.7rem; }
.privacy-inline { max-width: 560px; margin-top: 26px; padding-left: 18px; border-left: 3px solid var(--green); color: #3c5849; font-size: .9rem; }
.privacy-inline span { color: var(--green); }

.history-band { padding: 100px 0; background: #eaf0f7; }
.history-inner { width: min(calc(100% - 40px), 1040px); margin: auto; display: grid; grid-template-columns: 300px minmax(0, 1fr); align-items: center; gap: clamp(60px, 10vw, 140px); }
.history-device { position: relative; justify-self: center; width: 278px; padding: 12px; border: 1px solid #cfd8e3; border-radius: 28px; background: #f9fbfd; box-shadow: 0 30px 70px rgba(47,69,94,.2); }
.history-device::before { content: ""; position: absolute; left: 50%; top: 5px; width: 72px; height: 5px; transform: translateX(-50%); border-radius: 4px; background: #d7dee7; }
.history-device img { width: 100%; border-radius: 18px; }
.history-copy h2 { max-width: 600px; }
.history-copy > p:not(.eyebrow) { max-width: 580px; color: #536071; }
.history-points { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 28px; }
.history-points span { padding: 7px 12px; border: 1px solid #bcc8d6; border-radius: 999px; color: #45566b; font-size: .84rem; font-weight: 650; }

.plans { background: #fff; }
.plan-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 22px; align-items: stretch; }
.plan-card { position: relative; display: flex; flex-direction: column; min-height: 560px; padding: 36px; border: 1px solid var(--line); border-radius: 8px; background: #fff; }
.plan-card.featured { color: #fff; border-color: var(--ink); background: var(--ink); }
.recommended { position: absolute; right: 24px; top: 24px; padding: 5px 9px; border-radius: 4px; color: #062a1a; background: #49dc92; font-size: .75rem; font-weight: 800; }
.plan-name { margin-bottom: 32px; font-size: 1.15rem; font-weight: 760; }
.price { display: flex; align-items: baseline; gap: 8px; margin-bottom: 0; }
.price strong { font-size: 3rem; line-height: 1; }
.price strong small { font-size: 1.35rem; }
.price span { color: var(--muted); font-size: .88rem; }
.featured .price span { color: #9ca6b3; }
.price-options { display: grid; grid-template-columns: auto auto auto; align-items: center; gap: 18px; }
.or { color: #6f7782; font-size: .8rem; }
.check-list { flex: 1; padding: 36px 0 24px; margin: 34px 0 28px; border-top: 1px solid var(--line); list-style: none; }
.featured .check-list { border-color: #343941; }
.check-list li { position: relative; padding: 9px 0 9px 26px; }
.check-list li::before { content: "✓"; position: absolute; left: 0; top: 9px; color: var(--green); font-weight: 850; }
.coming em { margin-left: 7px; padding: 3px 6px; border-radius: 4px; color: #111; background: #f0c64a; font-size: .7rem; font-style: normal; font-weight: 800; }

.download-band { padding: 100px 0 34px; color: #fff; background: #0d1117; }
.download-inner { width: min(calc(100% - 40px), var(--content)); margin: auto; display: grid; grid-template-columns: 1.15fr .85fr; align-items: center; gap: 90px; }
.download-copy h2 { max-width: 660px; }
.download-copy > p:not(.eyebrow) { max-width: 600px; color: #9aa5b4; }
.download-actions { display: flex; align-items: center; flex-wrap: wrap; gap: 24px; margin-top: 32px; }
.text-link { color: #b6c0cd; border-bottom: 1px solid #596371; }
.requirements { border-top: 1px solid #343b45; }
.requirements div { display: grid; grid-template-columns: 96px minmax(0, 1fr); gap: 16px; padding: 18px 0; border-bottom: 1px solid #343b45; }
.requirements span { color: #7e8997; }
.requirements strong { font-weight: 650; }

.faq-inner { display: grid; grid-template-columns: .7fr 1.3fr; gap: 80px; }
.faq-list { border-top: 1px solid var(--line); }
.faq-list details { border-bottom: 1px solid var(--line); }
.faq-list summary { position: relative; padding: 24px 48px 24px 0; cursor: pointer; font-size: 1.04rem; font-weight: 700; list-style: none; }
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary span, .faq-list summary span::after { position: absolute; right: 5px; top: 50%; width: 16px; height: 2px; background: var(--ink); transform: translateY(-50%); }
.faq-list summary span::after { content: ""; right: 0; top: 0; transform: rotate(90deg); transition: transform .2s; }
.faq-list details[open] summary span::after { transform: rotate(0); }
.faq-list details p { max-width: 700px; padding: 0 48px 24px 0; margin: 0; color: var(--muted); }

.site-footer { padding: 54px 0 28px; border-top: 1px solid var(--line); background: #fff; }
.footer-inner { width: min(calc(100% - 40px), var(--content)); margin: auto; }
.footer-brand { display: flex; align-items: center; gap: 12px; }
.footer-brand div { display: flex; flex-direction: column; }
.footer-brand span { color: var(--muted); font-size: .8rem; }
.footer-links { display: flex; flex-wrap: wrap; gap: 24px; margin: 34px 0; font-size: .88rem; }
.footer-links a:hover { color: var(--blue); }
.copyright { margin: 0; color: #9097a1; font-size: .76rem; }

.reveal { opacity: 0; transform: translateY(18px); transition: opacity .55s ease, transform .55s ease; }
.reveal.visible { opacity: 1; transform: translateY(0); }

.legal-page { background: var(--mist); }
.legal-header { color: var(--ink); background: rgba(255,255,255,.96); border-color: var(--line); }
.legal-main { width: min(calc(100% - 40px), 860px); margin: 0 auto; padding: 140px 0 90px; }
.legal-main h1 { margin-bottom: 12px; font-size: clamp(2.6rem, 7vw, 4.8rem); }
.legal-meta { margin-bottom: 54px; color: var(--muted); }
.legal-content { padding: 44px; border: 1px solid var(--line); border-radius: 8px; background: #fff; }
.legal-content h2 { margin: 44px 0 12px; font-size: 1.45rem; }
.legal-content h2:first-child { margin-top: 0; }
.legal-content p, .legal-content li { color: #4e5661; }
.legal-content a { color: var(--blue); text-decoration: underline; }
.back-home { display: inline-flex; margin-top: 30px; color: var(--blue); font-weight: 700; }

.not-found { min-height: 100vh; display: grid; place-items: center; padding: 30px; text-align: center; background: var(--mist); }
.not-found img { width: 64px; height: 64px; margin: 0 auto 24px; }
.not-found h1 { margin-bottom: 10px; font-size: clamp(4rem, 14vw, 9rem); }
.not-found p { color: var(--muted); }

@media (max-width: 900px) {
  :root { --header: 62px; }
  .menu-toggle { display: block; }
  .main-nav { position: absolute; left: 0; right: 0; top: var(--header); display: none; align-items: stretch; gap: 0; padding: 12px 20px 20px; color: var(--ink); border-bottom: 1px solid var(--line); background: #fff; }
  .main-nav.open { display: flex; flex-direction: column; }
  .main-nav a { padding: 12px 4px; }
  .nav-github { margin-top: 8px; text-align: center; }
  .site-header.menu-open { color: var(--ink); background: #fff; }
  .menu-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
  .menu-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
  .menu-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }
  .showcase-inner, .showcase-inner.reverse { grid-template-columns: 1fr; gap: 54px; }
  .showcase-inner.reverse .showcase-copy, .showcase-inner.reverse .product-shot { order: initial; }
  .showcase-copy { max-width: 720px; }
  .history-inner { grid-template-columns: 260px 1fr; gap: 54px; }
  .history-device { width: 240px; }
  .download-inner { grid-template-columns: 1fr; gap: 58px; }
  .faq-inner { grid-template-columns: 1fr; gap: 20px; }
}

@media (max-width: 680px) {
  .header-inner, .hero-content, .section-inner, .showcase-inner, .history-inner, .download-inner, .footer-inner, .legal-main { width: min(calc(100% - 28px), var(--content)); }
  .brand { font-size: 1rem; }
  .hero { min-height: 91vh; background-position: 58% center; }
  .hero-content { padding-top: calc(var(--header) + 42px); padding-bottom: 74px; }
  .hero h1 { font-size: clamp(2.75rem, 13vw, 4rem); }
  .hero-copy { max-width: 520px; }
  .hero-actions { flex-direction: column; align-items: stretch; }
  .hero-actions .button { width: 100%; }
  .hero-meta { gap: 8px 0; }
  .section, .showcase { padding: 78px 0; }
  .section-heading { margin-bottom: 44px; }
  h2 { font-size: clamp(2rem, 11vw, 3.2rem); }
  .workflow-step { grid-template-columns: 48px minmax(0, 1fr); min-height: 150px; gap: 16px; }
  .showcase-copy h2 { font-size: clamp(2.25rem, 12vw, 3.5rem); }
  .product-shot.wide img { min-height: 270px; object-fit: cover; object-position: center; }
  .signal-row { gap: 24px; }
  .history-band { padding: 76px 0; }
  .history-inner { grid-template-columns: 1fr; gap: 52px; }
  .history-device { width: min(278px, 82vw); }
  .plan-grid { grid-template-columns: 1fr; }
  .plan-card { min-height: 0; padding: 28px 22px; }
  .recommended { position: static; width: max-content; margin: -8px 0 22px; }
  .price-options { grid-template-columns: 1fr; gap: 10px; }
  .or { display: none; }
  .requirements div { grid-template-columns: 76px minmax(0, 1fr); }
  .faq-list summary { padding-right: 38px; }
  .legal-content { padding: 28px 20px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; transition-duration: .01ms !important; }
  .reveal { opacity: 1; transform: none; }
}