:root {
  --canvas: #f6f8fb;
  --surface: #ffffff;
  --ink: #182840;
  --muted: #657489;
  --blue: #2563eb;
  --blue-hover: #1d4ed8;
  --selection: #ebf2ff;
  --line: #e2e8f0;
  --success: #1d8150;
  --radius: 12px;
  --max: 1180px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--canvas);
  font-family: "Microsoft YaHei UI", "Segoe UI", Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
button, .button { font: inherit; }

.site-header {
  position: sticky;
  z-index: 20;
  top: 0;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 max(24px, calc((100vw - var(--max)) / 2));
  background: rgba(255,255,255,.92);
  border-bottom: 1px solid rgba(218,218,223,.8);
  backdrop-filter: saturate(160%) blur(18px);
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; }
.brand img { border-radius: 8px; }
nav { display: flex; align-items: center; gap: 28px; font-size: 14px; }
nav a:hover { color: var(--blue); }
.nav-download { color: #fff; background: var(--blue); padding: 8px 16px; border-radius: 9px; }

.hero {
  max-width: var(--max);
  margin: 0 auto;
  padding: 96px 24px 72px;
  text-align: center;
}
.hero-copy { max-width: 900px; margin: 0 auto; }
.eyebrow { margin: 0 0 14px; color: var(--blue); font-size: 14px; font-weight: 700; }
h1, h2, h3, p { margin-top: 0; }
h1 { margin-bottom: 24px; font-size: clamp(40px, 6vw, 64px); line-height: 1.12; letter-spacing: -.045em; }
h2 { margin-bottom: 16px; font-size: clamp(30px, 4vw, 44px); line-height: 1.15; letter-spacing: -.035em; }
h3 { margin-bottom: 12px; font-size: 21px; line-height: 1.3; }
.lead { max-width: 720px; margin: 0 auto 30px; color: var(--muted); font-size: 18px; line-height: 1.8; }
.hero-actions { display: flex; justify-content: center; gap: 12px; margin-bottom: 26px; }
.button { display: inline-flex; min-height: 44px; align-items: center; justify-content: center; padding: 10px 20px; border-radius: 10px; font-weight: 600; transition: background .18s ease, color .18s ease, border-color .18s ease; }
.button.primary { color: #fff; background: var(--blue); }
.button.primary:hover { background: var(--blue-hover); }
.button.secondary { color: var(--blue); background: var(--surface); border: 1px solid var(--line); }
.button.secondary:hover { background: var(--selection); border-color: #b8d2ec; }
.release-meta { display: flex; justify-content: center; flex-wrap: wrap; gap: 10px 22px; color: var(--muted); font-size: 13px; }
.preview-shell { margin-top: 64px; padding: 10px; background: #fff; border: 1px solid var(--line); border-radius: 18px; box-shadow: 0 24px 70px rgba(29,29,31,.10); }
.preview-shell img { display: block; width: 100%; height: auto; border-radius: 10px; }

.trust-strip { max-width: var(--max); margin: 0 auto; display: grid; grid-template-columns: repeat(4,1fr); border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); }
.trust-strip div { display: flex; flex-direction: column; gap: 5px; padding: 22px 24px; border-right: 1px solid var(--line); }
.trust-strip div:last-child { border-right: 0; }
.trust-strip strong { font-size: 14px; }
.trust-strip span { color: var(--muted); font-size: 12px; }

.section { max-width: var(--max); margin: 0 auto; padding: 112px 24px; }
.section-heading { max-width: 700px; margin-bottom: 42px; }
.feature-grid { display: grid; grid-template-columns: repeat(2,1fr); gap: 18px; }
.feature-card { min-height: 240px; padding: 30px; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); }
.feature-card.featured { background: var(--selection); border-color: #bfd6ed; }
.feature-card p { color: var(--muted); line-height: 1.8; }
.icon { width: 40px; height: 40px; display: grid; place-items: center; margin-bottom: 36px; color: var(--blue); background: #fff; border: 1px solid var(--line); border-radius: 10px; font-size: 12px; font-weight: 700; }

.install { display: grid; grid-template-columns: .9fr 1.1fr; gap: 80px; align-items: start; }
.steps { margin: 0; padding: 0; list-style: none; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); }
.steps li { display: flex; gap: 18px; padding: 26px; border-bottom: 1px solid var(--line); }
.steps li:last-child { border-bottom: 0; }
.steps li > span { flex: 0 0 34px; width: 34px; height: 34px; display: grid; place-items: center; color: var(--blue); background: var(--selection); border-radius: 9px; font-weight: 700; }
.steps p { margin: 7px 0 0; color: var(--muted); line-height: 1.7; }

.download-section { padding: 72px max(24px, calc((100vw - var(--max)) / 2)); color: #fff; background: var(--ink); }
.download-section { display: grid; grid-template-columns: .8fr 1.2fr; gap: 64px; align-items: center; }
.download-section .eyebrow { color: #65adf5; }
.download-section p { color: #c9c9ce; line-height: 1.7; }
.download-card { color: var(--ink); background: var(--surface); border-radius: var(--radius); overflow: hidden; }
.file-row { display: flex; align-items: center; justify-content: space-between; gap: 20px; padding: 24px; }
.file-row div { display: flex; flex-direction: column; gap: 7px; min-width: 0; }
.file-row strong { overflow-wrap: anywhere; }
.file-row span { color: var(--muted); font-size: 13px; }
.hash-row { display: grid; grid-template-columns: auto 1fr auto; gap: 12px; align-items: center; padding: 16px 24px; background: var(--canvas); border-top: 1px solid var(--line); font-size: 12px; }
.hash-row code { overflow: hidden; color: var(--muted); text-overflow: ellipsis; white-space: nowrap; }
.hash-row button { color: var(--blue); background: transparent; border: 0; cursor: pointer; }

.changes ul { margin: 0; padding: 0; list-style: none; border-top: 1px solid var(--line); }
.changes li { padding: 20px 0; border-bottom: 1px solid var(--line); color: var(--muted); line-height: 1.7; }
.changes li strong { color: var(--ink); }
.release-date { margin-left: 0; text-align: left; }
.release-back { margin-top: 36px; }
footer { display: flex; justify-content: space-between; align-items: center; gap: 24px; padding: 42px max(24px, calc((100vw - var(--max)) / 2)); background: var(--surface); border-top: 1px solid var(--line); }
footer > div:first-child { display: flex; flex-direction: column; gap: 6px; }
footer span { color: var(--muted); font-size: 12px; }
.footer-links { display: flex; gap: 22px; color: var(--blue); font-size: 13px; }

@media (max-width: 860px) {
  nav a:not(.nav-download) { display: none; }
  .hero { padding-top: 72px; }
  .trust-strip { margin: 0 20px; grid-template-columns: repeat(2,1fr); }
  .trust-strip div:nth-child(2) { border-right: 0; }
  .trust-strip div:nth-child(-n+2) { border-bottom: 1px solid var(--line); }
  .install, .download-section { grid-template-columns: 1fr; gap: 32px; }
}
@media (max-width: 600px) {
  .site-header { height: 58px; }
  .brand span { font-size: 14px; }
  .hero { padding: 56px 18px 48px; }
  h1 { font-size: 38px; }
  .lead { font-size: 16px; }
  .hero-actions, .file-row { flex-direction: column; align-items: stretch; }
  .release-meta { flex-direction: column; }
  .preview-shell { margin-top: 42px; padding: 5px; border-radius: 12px; }
  .trust-strip, .feature-grid { grid-template-columns: 1fr; }
  .trust-strip div { border-right: 0; border-bottom: 1px solid var(--line); }
  .trust-strip div:last-child { border-bottom: 0; }
  .section { padding: 76px 20px; }
  .hash-row { grid-template-columns: 1fr auto; }
  .hash-row span { grid-column: 1 / -1; }
  footer { align-items: flex-start; flex-direction: column; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; }
}