:root {
  color-scheme: light;
  --canvas: #f4f5f0;
  --surface: #fcfcf8;
  --text: #202923;
  --muted: #657068;
  --line: #d7ddd4;
  --accent: #2e654d;
  --accent-hover: #204c39;
  --accent-soft: #e4ebe1;
  --on-accent: #ffffff;
  --dark-section: #202b24;
  --on-dark: #edf0e7;
  --paper: #fffdf7;
  --paper-text: #26332b;
  --paper-shadow: #dce1d6;
  --danger: #984b3e;
  --shell: 1400px;
  --gutter: clamp(24px, 4.5vw, 64px);
  --heading: "Segoe UI", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
  --mono: "Cascadia Mono", "SFMono-Regular", Consolas, monospace;
}

html[data-theme="dark"] {
  color-scheme: dark;
  --canvas: #171d19;
  --surface: #222923;
  --text: #e9ede4;
  --muted: #a7b1a7;
  --line: #3c473e;
  --accent: #b4d1ac;
  --accent-hover: #d0e4c9;
  --accent-soft: #2d3b30;
  --on-accent: #17251b;
  --dark-section: #111812;
  --on-dark: #edf0e7;
  --paper: #f5f3e9;
  --paper-text: #26332b;
  --paper-shadow: #0d130f;
  --danger: #e0a18e;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 24px; }
body {
  margin: 0;
  overflow-x: clip;
  color: var(--text);
  background: var(--canvas);
  font-family: var(--heading);
  font-size: 16px;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
button, select { font: inherit; }
button, summary, select { -webkit-tap-highlight-color: transparent; }
button { color: inherit; }
img { display: block; max-width: 100%; }
svg { display: block; }
p, h1, h2, h3, h4 { margin-top: 0; }
code { font-family: var(--mono); font-size: .9em; overflow-wrap: anywhere; }
::selection { color: var(--text); background: var(--accent-soft); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; }
[hidden] { display: none !important; }

.svg-defs { position: absolute; width: 0; height: 0; overflow: hidden; }
.icon { width: 20px; height: 20px; flex: 0 0 auto; fill: none; stroke: currentColor; stroke-width: 1.6; stroke-linecap: round; stroke-linejoin: round; }
.icon-fill { fill: currentColor; stroke: none; }
.shell { width: 100%; max-width: var(--shell); margin-inline: auto; padding-inline: var(--gutter); }
.region { padding: clamp(88px, 10vw, 150px) 0; scroll-margin-top: 20px; }
.skip-link { position: fixed; top: 10px; left: 10px; z-index: 1000; padding: 10px 16px; color: var(--on-accent); background: var(--accent); transform: translateY(-150%); }
.skip-link:focus { transform: translateY(0); }
.eyebrow { display: flex; align-items: center; gap: 10px; margin-bottom: 24px; color: var(--muted); font-family: var(--mono); font-size: 11px; line-height: 1.5; letter-spacing: .13em; text-transform: uppercase; }
.live-dot, .status-dot { display: inline-block; width: 7px; height: 7px; flex: 0 0 auto; background: var(--accent); border-radius: 50%; }
.chapter { display: flex; justify-content: space-between; align-items: baseline; gap: 24px; margin-bottom: clamp(48px, 6vw, 84px); padding-top: 16px; color: var(--muted); border-top: 1px solid var(--line); font-family: var(--mono); font-size: 10px; line-height: 1.7; letter-spacing: .11em; }
.chapter span:last-child { font-family: var(--heading); letter-spacing: .03em; }
.section-heading { display: flex; justify-content: space-between; align-items: flex-end; gap: 48px; margin-bottom: clamp(52px, 6vw, 84px); }
.section-heading h2, .open-grid h2, .faq-intro h2 { margin-bottom: 0; font-size: clamp(38px, 4.7vw, 66px); font-weight: 450; line-height: 1.17; letter-spacing: -.055em; }
h2 em, h1 em { color: var(--accent); font-style: normal; }
.section-heading > p { max-width: 370px; margin-bottom: 3px; color: var(--muted); font-size: 15px; line-height: 1.9; }
.text-link { display: inline-flex; align-items: center; gap: 14px; color: var(--accent); font-size: 14px; font-weight: 550; text-underline-offset: 5px; }
.text-link:hover { text-decoration: underline; }
.text-link .icon { width: 18px; height: 18px; }
.button { display: inline-flex; min-height: 50px; align-items: center; justify-content: center; gap: 11px; padding: 13px 20px; border: 1px solid transparent; border-radius: 3px; font-size: 14px; font-weight: 600; line-height: 1.4; transition: background-color .18s, border-color .18s, color .18s, transform .18s; }
.button:hover { transform: translateY(-2px); }
.button-primary { color: var(--on-accent); background: var(--accent); border-color: var(--accent); }
.button-primary:hover { background: var(--accent-hover); border-color: var(--accent-hover); }
.button-secondary { color: var(--text); background: transparent; border-color: var(--line); }
.button-secondary:hover { background: var(--surface); border-color: var(--muted); }

.site-header { position: relative; z-index: 50; background: var(--canvas); border-bottom: 1px solid var(--line); }
.site-header > .shell { display: flex; min-height: 92px; align-items: center; gap: 28px; }
.brand { display: inline-flex; flex: 0 0 auto; align-items: center; gap: 11px; }
.brand-mark { width: 38px; height: 38px; background: #fff; border: 1px solid var(--line); border-radius: 3px; }
.brand-name { font-size: 18px; font-weight: 650; line-height: 1; letter-spacing: -.035em; }
.brand-edition { margin-left: 5px; padding-left: 16px; color: var(--muted); border-left: 1px solid var(--line); font-family: var(--mono); font-size: 9px; letter-spacing: .15em; }
.site-nav { display: flex; align-items: center; gap: clamp(18px, 2.3vw, 34px); margin-left: auto; }
.site-nav a { position: relative; color: var(--muted); font-size: 13px; white-space: nowrap; }
.site-nav a:hover, .site-nav a[aria-current="page"] { color: var(--text); }
.site-nav a[aria-current="page"]::after { position: absolute; right: 0; bottom: -10px; left: 0; height: 1px; background: var(--accent); content: ""; }
.header-actions { display: flex; align-items: center; gap: 12px; margin-left: 8px; }
.github-link { display: inline-flex; align-items: center; gap: 7px; padding: 6px 10px; border: 1px solid var(--line); border-radius: 3px; font-size: 12px; line-height: 1.5; }
.github-link:hover { background: var(--surface); }
.github-link .icon { width: 16px; height: 16px; }
.language-switch { display: inline-flex; min-height: 38px; align-items: center; padding: 6px 8px; color: var(--accent); border: 1px solid var(--line); border-radius: 3px; font-size: 12px; white-space: nowrap; }
.language-switch:hover { background: var(--accent-soft); }
.theme-select { width: 82px; height: 34px; padding: 0 4px; color: var(--muted); background: transparent; border: 0; border-radius: 2px; font-size: 11px; cursor: pointer; }
.theme-select option { color: var(--text); background: var(--surface); }
.menu-toggle { display: none; width: 38px; height: 38px; place-items: center; padding: 0; background: transparent; border: 1px solid var(--line); border-radius: 3px; cursor: pointer; }
.menu-lines, .menu-lines::before, .menu-lines::after { display: block; width: 17px; height: 1px; background: currentColor; transition: transform .18s; }
.menu-lines { position: relative; }
.menu-lines::before, .menu-lines::after { position: absolute; left: 0; content: ""; }
.menu-lines::before { top: -5px; }
.menu-lines::after { top: 5px; }
.menu-toggle[aria-expanded="true"] .menu-lines { background: transparent; }
.menu-toggle[aria-expanded="true"] .menu-lines::before { top: 0; transform: rotate(45deg); }
.menu-toggle[aria-expanded="true"] .menu-lines::after { top: 0; transform: rotate(-45deg); }

.hero { position: relative; isolation: isolate; overflow: clip; padding: clamp(60px, 7vw, 100px) 0 0; }
.hero::before { position: absolute; top: 12%; right: -8%; z-index: -1; width: 48%; height: 68%; background: radial-gradient(ellipse, var(--accent-soft), transparent 70%); opacity: .65; content: ""; pointer-events: none; }
.hero-grid { display: grid; grid-template-columns: minmax(0, 1.03fr) minmax(380px, .97fr); align-items: center; gap: clamp(34px, 5vw, 78px); }
.hero-copy { padding-bottom: 34px; }
.hero h1 { max-width: 720px; margin-bottom: 30px; font-size: clamp(50px, 6.1vw, 86px); font-weight: 450; line-height: 1.09; letter-spacing: -.065em; }
.hero-lead { max-width: 520px; margin-bottom: 32px; color: var(--muted); font-size: clamp(15px, 1.35vw, 18px); line-height: 1.95; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }
.hero-actions .button-primary .icon:last-child { margin-left: 8px; }
.hero-mac-link { display: inline-flex; align-items: center; gap: 8px; margin-top: 20px; color: var(--muted); font-size: 12px; }
.hero-mac-link:hover { color: var(--accent); }
.hero-mac-link .icon { width: 15px; height: 15px; }
.hero-mac-link .icon:last-child { margin-left: 3px; }
.hero-note { margin: 26px 0 0; color: var(--muted); font-family: var(--mono); font-size: 10px; letter-spacing: .05em; }
.hero-visual { position: relative; min-width: 0; padding: 20px 0 62px 16px; }
.visual-index { position: absolute; top: -4px; right: 0; color: var(--muted); font-family: var(--mono); font-size: 9px; letter-spacing: .12em; }
.software-figure { position: relative; z-index: 1; margin: 0; padding: 11px; background: #fdfefb; border: 1px solid #c9d0c6; box-shadow: 12px 14px 0 var(--paper-shadow); transform: rotate(1.35deg); }
.software-figure::before, .software-figure::after { position: absolute; z-index: -1; background: var(--surface); border: 1px solid var(--line); content: ""; inset: 0; }
.software-figure::before { transform: rotate(-3deg) translate(-7px, 3px); }
.software-figure::after { transform: rotate(3.2deg) translate(8px, 1px); }
.software-topbar { display: flex; align-items: center; justify-content: space-between; padding: 2px 1px 11px; color: #5f6b62; font-family: var(--mono); font-size: 8px; letter-spacing: .11em; }
.window-dots { display: flex; gap: 5px; }
.window-dots i { width: 4px; height: 4px; background: #a9b4a8; border-radius: 50%; }
.software-figure > img { width: 100%; height: auto; border: 1px solid #e4e8e4; }
.software-figure figcaption { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 13px 2px 2px; color: #36463b; font-size: 10px; line-height: 1.5; }
.software-figure figcaption > span { display: flex; align-items: center; gap: 7px; }
.software-figure figcaption small { color: #758078; font-size: 9px; }
.signal-note { position: absolute; bottom: 1px; left: -12px; z-index: 2; display: flex; align-items: center; gap: 14px; color: var(--accent); }
.signal-note svg { width: 72px; height: 36px; fill: none; stroke: currentColor; stroke-width: 1.1; }
.signal-note span { font-family: var(--mono); font-size: 8px; line-height: 1.7; letter-spacing: .09em; }
.proof-strip { display: grid; grid-template-columns: repeat(3, 1fr) auto; align-items: center; gap: 24px; margin-top: clamp(48px, 6vw, 80px); padding: 26px 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.proof-strip > div { display: flex; align-items: flex-start; gap: 14px; }
.proof-number { padding-top: 3px; color: var(--accent); font-family: var(--mono); font-size: 9px; }
.proof-strip p { margin: 0; line-height: 1.5; }
.proof-strip strong { display: block; font-size: 13px; font-weight: 600; }
.proof-strip small { display: block; margin-top: 6px; color: var(--muted); font-size: 11px; }
.proof-strip > a { display: flex; align-items: center; gap: 14px; color: var(--accent); font-size: 12px; }
.proof-strip > a .icon { width: 24px; height: 24px; }

.signal-flow { display: grid; grid-template-columns: 1fr 100px 1fr 100px 1fr; align-items: center; padding: 42px 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.flow-node { text-align: center; }
.flow-icon { display: grid; width: 64px; height: 64px; place-items: center; margin: 0 auto 24px; color: var(--accent); border: 1px solid var(--line); border-radius: 50%; }
.flow-icon .icon { width: 26px; height: 26px; }
.flow-node-emphasis .flow-icon { background: var(--accent-soft); border-color: var(--accent); }
.flow-index { color: var(--muted); font-family: var(--mono); font-size: 9px; letter-spacing: .1em; }
.flow-node h3 { margin: 8px 0 12px; font-size: 24px; font-weight: 500; letter-spacing: -.025em; }
.flow-node p { margin-bottom: 0; color: var(--muted); font-size: 13px; line-height: 1.85; }
.flow-connector { position: relative; color: var(--accent); }
.flow-connector svg { width: 100%; fill: none; stroke: currentColor; stroke-width: 1; }
.flow-connector small { position: absolute; top: 22px; width: 100%; color: var(--muted); font-size: 9px; text-align: center; white-space: nowrap; }
.principles { display: grid; grid-template-columns: repeat(3, 1fr); }
.principles article { padding: 34px 34px 0 0; }
.principles article + article { padding-left: 34px; border-left: 1px solid var(--line); }
.principles article > span { color: var(--accent); font-size: 11px; }
.principles h3 { margin: 10px 0; font-size: 17px; font-weight: 600; }
.principles p { margin-bottom: 0; color: var(--muted); font-size: 13px; line-height: 1.85; }

.journey-region { --accent: #b4d1ac; --muted: #aab5aa; --line: #425047; color: var(--on-dark); background: var(--dark-section); }
.journey-region .chapter, .journey-region .section-heading > p { color: var(--muted); }
.journey-grid { display: grid; grid-template-columns: minmax(0, 1.13fr) minmax(330px, .87fr); align-items: center; gap: clamp(48px, 7vw, 100px); }
.journey-steps { margin: 0; padding: 0; border-top: 1px solid var(--line); list-style: none; }
.journey-steps li { display: grid; grid-template-columns: 42px 1fr auto; gap: 18px; align-items: start; padding: 26px 0; border-bottom: 1px solid var(--line); }
.journey-number { display: grid; width: 31px; height: 31px; place-items: center; margin-top: 4px; color: var(--accent); border: 1px solid var(--line); border-radius: 50%; font-family: var(--mono); font-size: 9px; }
.journey-steps small { color: var(--muted); font-family: var(--mono); font-size: 8px; letter-spacing: .12em; }
.journey-steps h3 { margin: 4px 0 8px; font-size: 21px; font-weight: 500; letter-spacing: -.025em; }
.journey-steps p { max-width: 450px; margin: 0; color: var(--muted); font-size: 13px; line-height: 1.8; }
.step-mark { align-self: center; color: var(--muted); font-size: 10px; white-space: nowrap; }
.acceptance-paper { --accent: #2e654d; --muted: #6b736b; position: relative; padding: clamp(28px, 3.5vw, 46px); color: var(--paper-text); background: var(--paper); box-shadow: 12px 14px 0 var(--paper-shadow); transform: rotate(-1.4deg); }
.acceptance-paper::after { position: absolute; right: 22px; bottom: 17px; width: 35px; height: 5px; border-top: 1px solid #bdc5b8; border-bottom: 1px solid #bdc5b8; content: ""; }
.paper-heading { display: flex; align-items: center; justify-content: space-between; padding-bottom: 17px; color: var(--muted); border-bottom: 1px solid #d8ddd2; font-family: var(--mono); font-size: 9px; letter-spacing: .11em; }
.paper-heading .icon { width: 19px; height: 19px; }
.paper-kicker { margin: 26px 0 8px; color: var(--accent); font-size: 11px; }
.acceptance-paper h3 { margin-bottom: 22px; font-size: clamp(26px, 2.8vw, 37px); font-weight: 450; line-height: 1.3; letter-spacing: -.04em; }
.acceptance-paper ul { margin: 0 0 24px; padding: 0; list-style: none; }
.acceptance-paper li { display: flex; align-items: center; gap: 12px; padding: 10px 0; border-bottom: 1px solid #e1e4dc; font-size: 13px; }
.acceptance-paper li > span { width: 13px; height: 13px; border: 1px solid #9daa9c; }
.paper-note { color: var(--muted); font-size: 11px; line-height: 1.8; }
.acceptance-paper .text-link { margin: 4px 0 18px; font-size: 12px; }
.validation-note { display: grid; grid-template-columns: auto 1fr auto; align-items: center; gap: 16px; margin-top: 80px; padding-top: 24px; border-top: 1px solid var(--line); }
.validation-note .status-dot { background: var(--accent); }
.validation-note p { margin: 0; font-size: 12px; }
.validation-note p strong { margin-right: 16px; font-weight: 600; }
.validation-note > small { color: var(--muted); font-size: 10px; }

.compatibility-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: clamp(26px, 3vw, 44px); }
.device-card { min-width: 0; padding-top: 24px; border-top: 1px solid var(--line); }
.device-card-top { display: flex; min-height: 60px; align-items: flex-start; justify-content: space-between; gap: 12px; }
.device-code { font-size: clamp(38px, 3.7vw, 53px); font-weight: 400; line-height: 1; letter-spacing: -.06em; }
.status { display: inline-block; padding: 3px 7px; border: 1px solid currentColor; border-radius: 2px; font-size: 9px; line-height: 1.5; white-space: nowrap; }
.status-verified { color: var(--accent); background: var(--accent-soft); }
.status-experimental { color: #8b671f; }
.status-paused { color: var(--danger); }
html[data-theme="dark"] .status-experimental { color: #d9bc78; }
.device-card h3 { margin: 23px 0 12px; font-size: 19px; font-weight: 550; }
.device-card > p { min-height: 100px; margin-bottom: 22px; color: var(--muted); font-size: 13px; line-height: 1.9; }
.device-card dl { margin: 0; border-top: 1px solid var(--line); }
.device-card dl > div { padding: 13px 0; border-bottom: 1px solid var(--line); }
.device-card dt { color: var(--muted); font-size: 10px; }
.device-card dd { margin: 3px 0 0; font-size: 12px; }
.requirement-row { display: flex; flex-wrap: wrap; align-items: center; gap: 14px 28px; margin-top: 48px; padding: 21px 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.requirement-row > span { margin-right: auto; color: var(--muted); font-family: var(--mono); font-size: 10px; letter-spacing: .08em; }
.requirement-row strong { position: relative; font-size: 11px; font-weight: 500; }
.requirement-row strong::before { display: inline-block; width: 4px; height: 4px; margin: 0 8px 2px 0; background: var(--accent); border-radius: 50%; content: ""; }
.risk-banner { display: grid; grid-template-columns: auto 1fr auto; align-items: center; gap: 20px; margin-top: 32px; padding: 22px 24px; background: var(--accent-soft); border-left: 2px solid var(--accent); }
.risk-banner > .icon { width: 27px; height: 27px; color: var(--accent); }
.risk-banner p { margin: 0; font-size: 12px; line-height: 1.8; }
.risk-banner p strong { display: block; }
.risk-banner > a { display: inline-flex; align-items: center; gap: 12px; color: var(--accent); font-size: 12px; white-space: nowrap; }

.download-region { background: var(--surface); }
.release-summary { min-width: 230px; }
.release-summary p { margin-bottom: 18px; color: var(--muted); font-size: 12px; line-height: 1.8; }
.release-summary strong { color: var(--text); font-family: var(--mono); font-size: 13px; font-weight: 500; }
.download-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
.download-card { min-width: 0; padding: clamp(28px, 3.4vw, 46px); background: var(--canvas); border: 1px solid var(--line); }
.platform-heading { display: flex; align-items: center; justify-content: space-between; margin-bottom: 32px; color: var(--muted); font-family: var(--mono); font-size: 9px; letter-spacing: .1em; }
.platform-icon { width: 27px; height: 27px; color: var(--text); }
.download-card h3 { margin-bottom: 4px; font-size: clamp(36px, 4vw, 52px); font-weight: 450; line-height: 1.2; letter-spacing: -.05em; }
.platform-spec { margin-bottom: 24px; color: var(--accent); font-family: var(--mono); font-size: 10px; }
.download-card > p:not(.platform-spec) { max-width: 450px; color: var(--muted); font-size: 13px; line-height: 1.9; }
.download-actions { display: flex; flex-direction: column; align-items: flex-start; gap: 16px; margin-top: 30px; }
.checksum-link { display: inline-flex; align-items: center; gap: 7px; color: var(--muted); font-size: 11px; text-decoration: underline; text-underline-offset: 4px; }
.checksum-link:hover { color: var(--accent); }
.checksum-link .icon { width: 13px; height: 13px; }
.package-note { display: block; margin-top: 28px; padding-top: 18px; color: var(--muted); border-top: 1px solid var(--line); font-size: 10px; line-height: 1.8; }
.source-download { display: flex; align-items: center; justify-content: space-between; gap: 30px; margin-top: 26px; padding: 22px 0; border-bottom: 1px solid var(--line); }
.source-download p { margin: 0; color: var(--muted); font-size: 12px; }
.source-download p strong { margin-right: 8px; color: var(--text); font-weight: 600; }
.source-download > div { display: flex; flex-wrap: wrap; gap: 18px; }
.source-download a { color: var(--accent); font-size: 11px; text-decoration: underline; text-underline-offset: 4px; }
.download-guide-link { margin: 28px 0 0; text-align: right; }

.open-grid { display: grid; grid-template-columns: 1fr auto; align-items: end; gap: 50px; }
.open-grid h2 { font-size: clamp(36px, 4.2vw, 59px); }
.open-grid p { margin: 24px 0 0; color: var(--muted); font-size: 14px; }
.star-actions { display: flex; flex-direction: column; align-items: flex-start; gap: 22px; padding-bottom: 7px; }
.star-actions .button { min-width: 225px; }
.open-facts { display: flex; flex-wrap: wrap; align-items: center; gap: 22px 34px; margin-top: 64px; padding: 24px 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.open-facts > span, .open-facts > a { display: inline-flex; align-items: center; gap: 8px; color: var(--muted); font-size: 11px; }
.open-facts .icon { width: 15px; height: 15px; color: var(--accent); }
.open-facts > a { margin-left: auto; color: var(--accent); }

.faq-layout { display: grid; grid-template-columns: minmax(0, .85fr) minmax(0, 1.15fr); gap: clamp(48px, 8vw, 120px); }
.faq-intro h2 { font-size: clamp(37px, 4vw, 56px); }
.faq-intro p { margin: 26px 0 30px; color: var(--muted); font-size: 13px; }
.faq-list { border-bottom: 1px solid var(--line); }
.faq-list details { border-top: 1px solid var(--line); }
.faq-list summary { position: relative; padding: 23px 42px 23px 0; font-size: 15px; font-weight: 500; line-height: 1.6; list-style: none; cursor: pointer; }
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary span::before, .faq-list summary span::after { position: absolute; top: 36px; right: 3px; width: 14px; height: 1px; background: var(--accent); content: ""; transition: transform .18s; }
.faq-list summary span::after { transform: rotate(90deg); }
.faq-list details[open] summary span::after { transform: rotate(0); }
.faq-list details p { margin: -4px 38px 24px 0; color: var(--muted); font-size: 13px; line-height: 1.9; }

.footer { padding: 54px 0 28px; background: var(--canvas); border-top: 1px solid var(--line); }
.footer > .shell { display: grid; grid-template-columns: 1fr auto; gap: 40px; }
.footer-brand p { margin: 13px 0 0; color: var(--muted); font-size: 12px; }
.footer-links { display: flex; flex-wrap: wrap; align-items: flex-start; gap: 24px; }
.footer-links a { display: inline-flex; align-items: center; gap: 5px; color: var(--muted); font-size: 12px; }
.footer-links a:hover { color: var(--accent); }
.footer-links .icon { width: 13px; height: 13px; }
.footer-bottom { display: flex; grid-column: 1 / -1; justify-content: space-between; gap: 24px; padding-top: 22px; color: var(--muted); border-top: 1px solid var(--line); font-size: 10px; }

.guide-hero .button-secondary { color: var(--on-dark); border-color: #637066; }
.guide-hero .button-secondary:hover { background: #ffffff0d; border-color: var(--on-dark); }

@media (max-width: 1100px) {
  .site-header > .shell { gap: 20px; }
  .brand-edition { display: none; }
  .hero-grid { gap: 30px; }
  .hero h1 { font-size: clamp(46px, 6.2vw, 68px); }
  .proof-strip { grid-template-columns: repeat(3, 1fr); }
  .proof-strip > a { grid-column: 1 / -1; justify-content: flex-end; }
  .signal-flow { grid-template-columns: 1fr 70px 1fr 70px 1fr; }
  .journey-grid { gap: 42px; }
  .journey-steps li { grid-template-columns: 36px 1fr; }
  .step-mark { grid-column: 2; margin-top: -8px; }
  .device-card > p { min-height: 125px; }
  .requirement-row > span { width: 100%; }
}

@media (max-width: 1100px) {
  .site-header > .shell { min-height: 80px; }
  .site-nav { position: absolute; top: 100%; right: var(--gutter); left: var(--gutter); display: none; gap: 0; margin: 0; padding: 14px 22px; background: var(--surface); border: 1px solid var(--line); box-shadow: 0 12px 28px #00000015; }
  .site-nav[data-open="true"] { display: grid; }
  .site-nav a { padding: 12px 0; border-bottom: 1px solid var(--line); }
  .site-nav a:last-child { border-bottom: 0; }
  .site-nav a[aria-current="page"]::after { display: none; }
  .header-actions { margin-left: auto; }
  .menu-toggle { display: grid; }
  .hero-grid { grid-template-columns: 1fr; }
  .hero-copy { max-width: 720px; padding-bottom: 0; }
  .hero h1 { font-size: clamp(56px, 9vw, 78px); }
  .hero-visual { width: 100%; max-width: 720px; margin: 0 auto; }
  .section-heading { display: block; }
  .section-heading > p { margin-top: 26px; }
  .signal-flow { grid-template-columns: 1fr; padding: 36px 0; }
  .flow-node { max-width: 480px; margin: 0 auto; }
  .flow-connector { width: 60px; height: 72px; margin: 0 auto; }
  .flow-connector svg { width: 28px; height: 58px; margin: 0 auto; transform: rotate(90deg); }
  .flow-connector small { display: none; }
  .principles { grid-template-columns: 1fr; }
  .principles article, .principles article + article { padding: 26px 0; border-left: 0; border-bottom: 1px solid var(--line); }
  .principles article:last-child { border-bottom: 0; }
  .journey-grid { grid-template-columns: 1fr; }
  .journey-steps li { grid-template-columns: 42px 1fr auto; }
  .step-mark { grid-column: auto; margin-top: 0; }
  .acceptance-paper { width: 100%; max-width: 530px; margin: 16px auto; }
  .validation-note { grid-template-columns: auto 1fr; }
  .validation-note > small { grid-column: 2; }
  .compatibility-grid { grid-template-columns: 1fr; gap: 40px; }
  .device-card > p { min-height: 0; }
  .device-card dl { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
  .download-grid { grid-template-columns: 1fr; }
  .source-download { align-items: flex-start; flex-direction: column; }
  .open-grid { grid-template-columns: 1fr; }
  .star-actions { flex-direction: row; align-items: center; flex-wrap: wrap; }
  .open-facts > a { width: 100%; margin-left: 0; }
  .faq-layout { grid-template-columns: 1fr; }
}

@media (max-width: 600px) {
  :root { --gutter: 21px; }
  .region { padding: 80px 0; }
  .chapter { align-items: flex-start; flex-direction: column; gap: 6px; margin-bottom: 44px; }
  .section-heading { margin-bottom: 48px; }
  .section-heading h2, .open-grid h2, .faq-intro h2 { font-size: clamp(34px, 10vw, 46px); }
  .site-header > .shell { flex-wrap: wrap; gap: 10px; padding-block: 14px; }
  .header-actions { width: 100%; justify-content: flex-end; }
  .header-actions .language-switch { margin-right: auto; }
  .brand { gap: 8px; }
  .brand-mark { width: 34px; height: 34px; }
  .brand-name { font-size: 16px; }
  .header-actions { gap: 6px; }
  .github-link { padding: 6px 8px; }
  .github-link > span { display: none; }
  .theme-select { width: 72px; font-size: 10px; }
  .hero { padding-top: 52px; }
  .hero .eyebrow { font-size: 9px; letter-spacing: .09em; }
  .hero h1 { margin-bottom: 24px; font-size: clamp(43px, 13vw, 65px); }
  .hero-lead { font-size: 15px; }
  .hero-actions { flex-direction: column; }
  .hero-actions .button { width: 100%; }
  .hero-visual { padding: 12px 0 30px; }
  .software-figure { padding: 7px; box-shadow: 6px 7px 0 var(--paper-shadow); }
  .software-figure figcaption { align-items: flex-start; font-size: 9px; }
  .software-figure figcaption small { max-width: 70px; text-align: right; }
  .signal-note { position: relative; bottom: auto; left: auto; margin: 28px 0 0 10px; }
  .proof-strip { grid-template-columns: 1fr; gap: 20px; margin-top: 40px; }
  .proof-strip > a { grid-column: auto; justify-content: space-between; padding-top: 18px; border-top: 1px solid var(--line); }
  .flow-node p br { display: none; }
  .journey-steps li { grid-template-columns: 34px 1fr; gap: 13px; }
  .step-mark { grid-column: 2; margin-top: -5px; }
  .acceptance-paper { padding: 28px 25px; box-shadow: 6px 7px 0 var(--paper-shadow); }
  .validation-note { margin-top: 58px; }
  .validation-note p strong { display: block; margin: 0 0 5px; }
  .device-card dl { grid-template-columns: 1fr; gap: 0; }
  .requirement-row { align-items: flex-start; flex-direction: column; gap: 10px; }
  .risk-banner { grid-template-columns: auto 1fr; padding: 20px; }
  .risk-banner > a { grid-column: 2; }
  .release-summary { margin-top: 28px; }
  .download-card { padding: 28px 24px; }
  .download-actions .button { width: 100%; }
  .source-download { gap: 20px; }
  .source-download p strong { display: block; margin-bottom: 6px; }
  .download-guide-link { text-align: left; }
  .star-actions { align-items: flex-start; flex-direction: column; }
  .open-facts { align-items: flex-start; flex-direction: column; }
  .faq-list summary { font-size: 14px; }
  .footer > .shell { grid-template-columns: 1fr; gap: 30px; }
  .footer-links { gap: 18px 24px; }
  .footer-bottom { align-items: flex-start; flex-direction: column; gap: 8px; }
}

@media (max-width: 370px) {
  :root { --gutter: 17px; }
  .site-header > .shell { gap: 7px; }
  .brand-name { font-size: 14px; }
  .theme-select { width: 65px; padding: 0; }
  .menu-toggle { width: 34px; height: 34px; }
  .hero h1 { font-size: 41px; }
  .button { padding-inline: 15px; }
}

/* Keep navigation available when scripting is disabled. */
@media (max-width: 1100px) {
  html:not([data-enhanced]) .site-header > .shell { flex-wrap: wrap; padding-block: 14px; }
  html:not([data-enhanced]) .site-nav { position: static; display: grid; flex-basis: 100%; order: 3; }
  html:not([data-enhanced]) .menu-toggle { display: none; }
}

/* English needs room to wrap naturally rather than inheriting Chinese line lengths. */
html:lang(en) .hero h1 { font-size: clamp(42px, 5.2vw, 74px); letter-spacing: -.045em; }
html:lang(en) h2 { overflow-wrap: anywhere; }
html:lang(en) .section-heading h2,
html:lang(en) .open-grid h2,
html:lang(en) .faq-intro h2 { font-size: clamp(34px, 4.3vw, 60px); letter-spacing: -.04em; }
html:lang(en) .journey-steps li { grid-template-columns: 36px minmax(0, 1fr); }
html:lang(en) .step-mark { grid-column: 2; margin-top: -8px; white-space: normal; }
html:lang(en) .flow-node { min-width: 0; padding-inline: 8px; }
html:lang(en) .flow-connector small { white-space: normal; }
html:lang(en) .validation-note { grid-template-columns: auto minmax(0, 1fr); }
html:lang(en) .validation-note > small { grid-column: 2; }
html:lang(en) .section-heading > * { min-width: 0; }
html:lang(en) .release-summary { flex-shrink: 0; }
html:lang(en) .acceptance-paper li > span { flex-shrink: 0; }
html:lang(en) .risk-banner { grid-template-columns: auto minmax(0, 1fr); }
html:lang(en) .risk-banner > a { grid-column: 2; }
@media (max-width: 600px) {
  html:lang(en) .hero h1 { font-size: clamp(39px, 10.5vw, 60px); }
  html:lang(en) .hero-lead br,
  html:lang(en) .section-heading > p br { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { scroll-behavior: auto !important; transition: none !important; }
  .button:hover { transform: none; }
}