:root {
  color-scheme: light dark;
  --canvas: #f5f7fa;
  --surface: #ffffff;
  --ink: #111b2c;
  --muted: #5f6d7e;
  --line: #d9e0e8;
  --accent: #315b8c;
  --accent-deep: #23456e;
  --accent-soft: #e8eef6;
  --dark: #101b2d;
  --on-dark: #f6f8fb;
  --on-dark-muted: #bdc9d7;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  font-synthesis: none;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--canvas); color: var(--ink); font-size: 16px; line-height: 1.75; overflow-wrap: anywhere; }
a { color: var(--accent-deep); text-underline-offset: .24em; }
img { display: block; max-width: 100%; }
::selection { background: var(--accent); color: #fff; }
:focus-visible { outline: 3px solid var(--accent); outline-offset: 4px; }
.shell { width: min(100% - 40px, 1080px); margin-inline: auto; }
.skip-link { position: fixed; top: 8px; left: 8px; z-index: 10; min-height: 44px; display: inline-flex; align-items: center; padding: 8px 13px; background: var(--dark); color: var(--on-dark); transform: translateY(-160%); }
.skip-link:focus { transform: translateY(0); }

.site-header { border-bottom: 1px solid var(--line); }
.nav { min-height: 76px; display: flex; align-items: center; justify-content: space-between; gap: 22px; }
.brand { display: inline-flex; align-items: center; gap: 11px; color: var(--ink); font-weight: 820; text-decoration: none; }
.brand img { width: 40px; height: 40px; border-radius: 12px; }
.nav-links { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 6px 18px; }
.nav-links a { min-height: 44px; display: inline-flex; align-items: center; color: var(--muted); font-size: .9rem; font-weight: 650; text-decoration: none; }
.nav-links a:hover, .nav-links a[aria-current="page"] { color: var(--accent); }

.hero { min-height: 590px; display: grid; grid-template-columns: minmax(0, 1.15fr) minmax(260px, .85fr); align-items: center; gap: clamp(48px, 8vw, 110px); padding-block: clamp(70px, 10vw, 122px); }
.hero h1 { max-width: 15ch; margin: 0; font-size: clamp(3rem, 5.3vw, 4.6rem); font-weight: 680; letter-spacing: -.04em; line-height: 1.02; text-wrap: balance; }
.hero h1 span { display: block; white-space: nowrap; }
.hero-copy > p:not(.eyebrow):not(.download-note) { max-width: 42rem; margin: 26px 0 0; color: var(--muted); font-size: clamp(1.03rem, 1.6vw, 1.2rem); }
.hero-identity { padding: clamp(28px, 5vw, 52px); border-radius: 28px; background: var(--dark); color: var(--on-dark); }
.hero-identity img { width: 148px; height: 148px; border-radius: 34px; box-shadow: 0 22px 50px rgba(0,0,0,.28); }
.hero-identity p { margin: 42px 0 0; color: var(--on-dark-muted); font-size: 1.05rem; line-height: 1.9; }
.actions { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; margin-top: 28px; }
.button { min-height: 48px; display: inline-flex; align-items: center; justify-content: center; padding: 10px 18px; border-radius: 10px; font-weight: 760; text-decoration: none; }
.button-primary { background: var(--accent); color: #fff; transition: background 160ms ease, transform 160ms ease; }
.button-primary:hover { background: var(--accent-deep); color: #fff; transform: translateY(-2px); }
.button-disabled { border: 1px solid var(--line); color: var(--muted); cursor: default; }
.text-link { min-height: 48px; display: inline-flex; align-items: center; padding-inline: 8px; font-weight: 720; }
.download-note { margin: 14px 0 0; color: var(--muted); font-family: ui-monospace, Consolas, monospace; font-size: .78rem; }

.section { border-top: 1px solid var(--line); }
.section-grid, .safety-grid { display: grid; grid-template-columns: minmax(240px, .8fr) minmax(0, 1.2fr); gap: clamp(42px, 8vw, 118px); padding-block: clamp(62px, 9vw, 104px); }
.section h2, .release h2, .safety-band h2 { max-width: 11ch; margin: 0; font-size: clamp(2.15rem, 4.8vw, 4.3rem); font-weight: 660; letter-spacing: -.04em; line-height: 1.03; text-wrap: balance; }
.release h2 { max-width: 14ch; }
.release h2 span { display: block; white-space: nowrap; }
.section-intro { max-width: 28rem; margin: 22px 0 0; color: var(--muted); }
.process-list { margin: 0; padding: 0; list-style: none; }
.process-list li { display: grid; grid-template-columns: 44px 1fr; gap: 18px; padding: 0 0 26px; margin-bottom: 26px; border-bottom: 1px solid var(--line); }
.process-list li:last-child { margin: 0; padding: 0; border: 0; }
.process-list span { color: var(--accent); font-size: .78rem; font-weight: 800; }
.process-list h3 { margin: 0 0 7px; font-size: 1.15rem; }
.process-list p { margin: 0; color: var(--muted); }

.release { display: grid; grid-template-columns: minmax(240px, .8fr) minmax(0, 1.2fr); gap: clamp(42px, 8vw, 118px); padding-block: clamp(62px, 9vw, 104px); }
.release-detail p { margin: 0 0 18px; color: var(--muted); }
.release-detail code { display: block; padding: 18px; border-radius: 12px; background: var(--surface); color: var(--muted); font-family: ui-monospace, Consolas, monospace; font-size: .8rem; line-height: 1.8; }
.release-detail .button { margin-top: 20px; }
.safety-band { background: var(--dark); color: var(--on-dark); }
.safety-grid > p { margin: 0; color: var(--on-dark-muted); font-size: 1.04rem; }

.reading { max-width: 800px; margin: 48px auto 80px; padding: clamp(26px, 5vw, 56px); border-radius: 22px; background: var(--surface); }
.page-title, .reading h1 { margin: 0; font-size: clamp(2.35rem, 6vw, 4.6rem); font-weight: 680; letter-spacing: -.04em; line-height: 1.04; }
.reading .meta { margin: 12px 0 32px; color: var(--muted); font-size: .92rem; }
.reading h2 { margin: 34px 0 9px; color: var(--accent); font-size: 1.28rem; }
.reading h3 { margin: 25px 0 7px; font-size: 1.06rem; }
.reading p, .reading li { color: var(--muted); }
.reading ul, .reading ol { padding-left: 1.4em; }
.reading .notice { margin-top: 28px; padding: 18px 20px; border: 1px solid var(--line); background: var(--accent-soft); color: var(--ink); }
.reading details { margin-top: 12px; padding: 14px 16px; border: 1px solid var(--line); border-radius: 10px; }
.reading summary { min-height: 44px; display: flex; align-items: center; cursor: pointer; color: var(--accent); font-weight: 760; }

.site-footer { border-top: 1px solid var(--line); }
.footer-grid { min-height: 118px; display: flex; align-items: flex-start; justify-content: space-between; gap: 28px; padding-block: 30px; color: var(--muted); font-size: .9rem; }
.footer-grid p { margin: 0; }
.footer-grid nav { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 8px 20px; }
.footer-grid nav a, .site-footer > .shell > p a { min-height: 44px; display: inline-flex; align-items: center; }

@media (max-width: 760px) {
  .shell { width: min(100% - 28px, 680px); }
  .nav { align-items: flex-start; flex-direction: column; padding-block: 16px; }
  .nav-links { justify-content: flex-start; }
  .hero { min-height: auto; grid-template-columns: 1fr; gap: 38px; padding-block: 54px 68px; }
  .hero h1 { font-size: clamp(2.4rem, 10.2vw, 3.8rem); }
  .hero-identity { display: grid; grid-template-columns: 96px 1fr; align-items: center; gap: 22px; }
  .hero-identity img { width: 96px; height: 96px; border-radius: 24px; }
  .hero-identity p { margin: 0; }
  .section-grid, .release, .safety-grid { grid-template-columns: 1fr; }
  .section h2, .release h2, .safety-band h2 { max-width: 14ch; }
  .footer-grid { flex-direction: column; }
  .footer-grid nav { justify-content: flex-start; }
}

@media (max-width: 500px) {
  .actions { align-items: stretch; flex-direction: column; }
  .button, .text-link { width: 100%; }
  .hero-identity { grid-template-columns: 76px 1fr; padding: 24px; }
  .hero-identity img { width: 76px; height: 76px; border-radius: 19px; }
  .reading { margin-top: 24px; }
}

@media (prefers-color-scheme: dark) {
  :root {
    --canvas: #0b121d;
    --surface: #101a28;
    --ink: #f1f5fa;
    --muted: #a5b2c3;
    --line: #273549;
    --accent: #76a4d7;
    --accent-deep: #8db5e1;
    --accent-soft: #1a2d43;
    --dark: #07101b;
  }
  .button-primary { color: #07101b; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .button-primary { transition: none; }
  .button-primary:hover { transform: none; }
}