:root {
  --bg: #f5f9fb;
  --bg-panel: #ffffff;
  --bg-panel-2: #eef3f6;
  --border: #dde5ea;
  --accent: #2e8540;
  --accent-hover: #26723a;
  --accent-dark: #11706b;
  --accent-tint: #e6f2e9;
  --teal-tint: #e2f0ef;
  --text: #2b3a44;
  --text-muted: #64737e;
  --success: #2e8540;
  --warn: #b7790f;
  --warn-ink: #80520b;
  --error: #c2453b;
  --on-accent: #ffffff;
  --glow: #ffffff;
  --clear: transparent;
  --mask-solid: #000000;
  --band-bg: rgba(255, 255, 255, .62);
  --veil-bg: rgba(43, 58, 68, .28);
  --shadow-nav: 0 1px 0 rgba(43, 58, 68, .03), 0 2px 10px rgba(43, 58, 68, .035);
  --shadow-card: 0 1px 2px rgba(43, 58, 68, .04), 0 6px 18px rgba(43, 58, 68, .045), 0 22px 48px -18px rgba(43, 58, 68, .07);
  --shadow-btn: 0 1px 2px rgba(17, 52, 30, .18), 0 4px 12px -4px rgba(46, 133, 64, .35);
  --shadow-chip: 0 1px 2px rgba(43, 58, 68, .05);
  --ring-dot: 0 0 0 4px rgba(46, 133, 64, .14);
  --focus: 0 0 0 3px rgba(17, 112, 107, .28);
  --radius: 6px;
  --radius-sm: 4px;
  --radius-logo: 9px;
  --radius-shot: 10px;
  --radius-pill: 999px;
  --radius-circle: 50%;
  --font-display: "Inter", "Noto Sans SC", "PingFang SC", "Hiragino Sans", "Apple SD Gothic Neo", "Microsoft YaHei", system-ui, sans-serif;
  --font-body: "Inter", "Noto Sans SC", "PingFang SC", "Hiragino Sans", "Apple SD Gothic Neo", "Microsoft YaHei", system-ui, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  --weight-regular: 400;
  --weight-medium: 500;
  --weight-bold: 700;
  --size-xs: 12px;
  --size-label: 12.5px;
  --size-badge: 13px;
  --size-device: 13.5px;
  --size-sm: 14px;
  --size-nav: 14.5px;
  --size-button: 15px;
  --size-body: 16px;
  --size-h3: 18px;
  --size-lead: 20px;
  --size-h2: 28px;
  --size-h1: clamp(34px, 3.4vw, 48px);
  --size-art: 11.5px;
  --size-art-code: 11px;
  --size-art-rule: 10.5px;
  --tracking-heading: -.015em;
  --tracking-label: .04em;
  --leading-body: 1.6;
  --leading-title: 1.18;
  --gutter: 40px;
  --shell: 1160px;
  --reading: 840px;
  --header-content: 1280px;
  --header-height: 64px;
  --section-space: 120px;
  --duration-fast: .15s;
  --duration-reveal: .5s;
  --duration-pulse: 4s;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 24px; }
html, body { margin: 0; padding: 0; }
html.nav-open { overflow: hidden; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: var(--size-body);
  font-weight: var(--weight-regular);
  line-height: var(--leading-body);
  -webkit-font-smoothing: antialiased;
}
main, section, article, aside, nav, header, footer, div { min-width: 0; }
img, svg { max-width: 100%; }
img { display: block; }
svg { display: block; }
button, input, select, textarea { font: inherit; }
button { cursor: pointer; }
a { color: var(--accent-dark); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }
button:focus-visible, a:focus-visible, summary:focus-visible, [tabindex]:focus-visible {
  outline: 2px solid var(--accent-dark);
  outline-offset: 3px;
  box-shadow: var(--focus);
  border-radius: var(--radius-sm);
}
button:disabled, .btn[aria-disabled="true"] { cursor: not-allowed; }
[hidden] { display: none !important; }
h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: var(--weight-regular);
  letter-spacing: var(--tracking-heading);
  line-height: 1.3;
  text-wrap: balance;
  margin-top: 0;
}
h1 { font-size: var(--size-h1); line-height: var(--leading-title); }
h2 { font-size: var(--size-h2); }
h3, h4 { font-size: var(--size-h3); }
p { margin-top: 0; margin-bottom: 1em; }
strong, b { font-weight: var(--weight-medium); }
code, pre, kbd { font-family: var(--font-mono); }
code { overflow-wrap: anywhere; }
pre {
  max-width: 100%;
  min-width: 0;
  overflow-x: auto;
  padding: 20px;
  background: var(--bg-panel-2);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: var(--size-sm);
  line-height: 1.8;
  tab-size: 2;
}
pre code { white-space: pre; overflow-wrap: normal; word-break: normal; }
hr { border: 0; border-top: 1px solid var(--border); margin-block: 32px; }
.shell, .wrap {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.reading { max-width: var(--reading); }
.section { padding-top: var(--section-space); padding-bottom: var(--section-space); }
.section--band { background: var(--bg-panel-2); color: var(--text); }
.section-head { margin-bottom: 40px; }
.section-head p { max-width: 660px; color: var(--text-muted); }
.center { text-align: center; }
.center p { margin-inline: auto; }
.keep { white-space: nowrap; }
.muted { color: var(--text-muted); }
.eyebrow {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--size-label);
  letter-spacing: .08em;
  color: var(--accent-dark);
  margin-bottom: 8px;
}
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}
.skip-link {
  position: fixed;
  top: 8px;
  left: var(--gutter);
  z-index: 100;
  padding: 10px 16px;
  background: var(--bg-panel);
  color: var(--accent-dark);
  border-radius: var(--radius);
  transform: translateY(-160%);
}
.skip-link:focus { transform: none; }
.grid-two { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 24px; }
.grid-two > *, .card-grid > * { min-width: 0; }
.card-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 24px; }
.card, .panel {
  padding: 28px;
  background: var(--bg-panel);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
}
.card > :last-child, .panel > :last-child { margin-bottom: 0; }
.card h3 { margin-bottom: 12px; }
.prose { min-width: 0; }
.prose h2 { margin-top: 64px; margin-bottom: 20px; }
.prose h3 { margin-top: 32px; margin-bottom: 14px; }
.prose p, .prose li { line-height: 1.9; }
.prose ul, .prose ol { padding-left: 1.5em; }
.prose > :first-child { margin-top: 0; }
.prose img { max-width: 100%; height: auto; }
.prose figure { max-width: 100%; }
.prose blockquote { margin-inline: 0; }
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  min-width: 0;
  min-height: 46px;
  padding: 10px 24px;
  border: 1px solid var(--clear);
  border-radius: var(--radius);
  font-family: var(--font-body);
  font-size: var(--size-button);
  font-weight: var(--weight-medium);
  line-height: 1.5;
  letter-spacing: .005em;
  text-align: center;
  transition: background-color var(--duration-fast), color var(--duration-fast), border-color var(--duration-fast);
}
.btn:hover { text-decoration: none; }
.btn svg { width: 16px; height: 16px; flex-shrink: 0; }
.btn--store { background: var(--accent); color: var(--on-accent); box-shadow: var(--shadow-btn); }
.btn--store:hover, .btn--store.is-hover { background: var(--accent-hover); color: var(--on-accent); }
.btn--store:active, .btn--store.is-active { background: var(--accent-dark); color: var(--on-accent); box-shadow: none; }
.btn--guide { border-color: var(--accent-dark); color: var(--accent-dark); background: var(--bg-panel); }
.btn--guide:hover { background: var(--teal-tint); color: var(--accent-dark); }
.btn--quiet { background: var(--bg-panel-2); color: var(--accent-dark); border-color: var(--border); }
.btn:disabled, .btn[aria-disabled="true"] {
  background: var(--bg-panel-2);
  color: var(--text-muted);
  border-color: var(--border);
  box-shadow: none;
}
.btn.is-focus { outline: 2px solid var(--accent-dark); outline-offset: 3px; box-shadow: var(--focus); }
.button-row { display: flex; flex-wrap: wrap; align-items: center; gap: 14px; }
.ctas { display: flex; justify-content: center; gap: 14px; margin-top: 22px; }

/* 独立宽版心；品牌、桌面导航、工具、抽屉是兄弟节点。 */
.topbar {
  position: relative;
  z-index: 40;
  height: var(--header-height);
  background: var(--bg-panel);
  color: var(--text);
  border-bottom: 1px solid var(--border);
  box-shadow: var(--shadow-nav);
}
.topbar__in {
  max-width: min(100%, calc(var(--header-content) + var(--gutter) * 2));
  height: 100%;
  margin-inline: auto;
  padding-inline: var(--gutter);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.brandmark { display: flex; align-items: center; gap: 11px; color: var(--text); min-width: 0; flex-shrink: 1; }
.brandmark__name { min-width: 0; overflow-wrap: anywhere; line-height: 1.3; }
.brandmark:hover { text-decoration: none; }
.brandmark__tile, .brandmark__logo {
  width: 32px;
  height: 32px;
  flex-shrink: 0;
  border-radius: var(--radius-logo);
}
.brandmark__tile {
  background: linear-gradient(160deg, var(--bg-panel), var(--bg-panel-2));
  color: var(--text);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-chip);
}
.brandmark__name { font-size: var(--size-button); font-weight: var(--weight-medium); letter-spacing: -.005em; }
.navline { min-width: 0; margin-left: auto; }
.navline__list { display: flex; align-items: center; list-style: none; margin: 0; padding: 0; }
.navline__list li { display: flex; align-items: center; flex-shrink: 0; }
.navline__list li + li::before {
  content: "·";
  color: var(--border);
  font-weight: var(--weight-bold);
  margin-inline: 12px;
}
.navline__list a {
  font-size: var(--size-nav);
  color: var(--text-muted);
  padding-block: 4px;
  white-space: nowrap;
  transition: color var(--duration-fast);
}
.navline__list a:hover, .navline__list a[aria-current="page"] { color: var(--accent-dark); text-decoration: none; }
.header-tools { display: flex; align-items: center; gap: 10px; flex-shrink: 0; }
.language-box { position: relative; }
.langpick {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  min-height: 44px;
  padding: 4px 0 4px 20px;
  font-family: var(--font-body);
  font-size: var(--size-sm);
  color: var(--text-muted);
  background: var(--clear);
  border: 0;
  border-left: 1px solid var(--border);
  white-space: nowrap;
}
.langpick__caret { font-size: var(--size-art-code); }
.language-menu {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  width: 190px;
  padding: 6px;
  margin: 0;
  list-style: none;
  background: var(--bg-panel);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
  z-index: 45;
}
.language-menu a { display: block; min-height: 44px; padding: 10px 12px; border-radius: var(--radius-sm); }
.language-menu a:hover, .language-menu a[aria-current="true"] { background: var(--bg-panel-2); color: var(--accent-dark); text-decoration: none; }
.menu-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  min-width: 44px;
  min-height: 44px;
  padding: 8px;
  background: var(--bg-panel);
  color: var(--accent-dark);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.menu-toggle svg { width: 22px; height: 22px; fill: none; stroke: currentColor; stroke-width: 1.5; }
.mobile-nav {
  position: absolute;
  z-index: 43;
  top: var(--header-height);
  left: 0;
  right: 0;
  padding: 16px var(--gutter) 24px;
  max-height: calc(100dvh - var(--header-height));
  overflow-y: auto;
  overscroll-behavior: contain;
  background: var(--bg-panel);
  color: var(--text);
  border-bottom: 1px solid var(--border);
  box-shadow: var(--shadow-card);
}
.mobile-nav ul { list-style: none; margin: 0; padding: 0; }
.mobile-nav a { display: flex; align-items: center; width: 100%; min-height: 48px; padding: 12px; border-radius: var(--radius-sm); }
.mobile-nav a:hover, .mobile-nav a[aria-current] { background: var(--bg-panel-2); color: var(--accent-dark); text-decoration: none; }
.mobile-nav__languages { border-top: 1px solid var(--border); margin-top: 12px; padding-top: 12px; }
.mobile-nav__title { margin: 0 12px 4px; font-size: var(--size-xs); color: var(--text-muted); }
.nav-veil { position: fixed; inset: var(--header-height) 0 0; z-index: 41; background: var(--veil-bg); color: var(--text); border: 0; cursor: default; }

/* 已确认的居中标题、双流程卡和全宽事实带。 */
.lede { position: relative; isolation: isolate; overflow-x: clip; padding-top: 40px; padding-bottom: 0; text-align: center; }
.lede::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -2;
  pointer-events: none;
  background-image: radial-gradient(circle, var(--border) 1.1px, var(--clear) 1.5px);
  background-size: 24px 24px;
  background-position: 12px 6px;
  opacity: .35;
  -webkit-mask-image: radial-gradient(ellipse 68% 62% at 50% 46%, var(--mask-solid) 30%, var(--clear) 78%);
  mask-image: radial-gradient(ellipse 68% 62% at 50% 46%, var(--mask-solid) 30%, var(--clear) 78%);
}
.lede__glow {
  position: absolute;
  z-index: -1;
  left: 50%;
  top: 330px;
  width: 1420px;
  height: 680px;
  transform: translateX(-50%);
  background: radial-gradient(closest-side, var(--glow) 0%, var(--glow) 38%, var(--clear) 100%);
  color: var(--text);
  opacity: .92;
  pointer-events: none;
}
.provenance {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-height: 30px;
  max-width: 100%;
  padding: 3px 14px 3px 12px;
  background: var(--bg-panel);
  color: var(--text-muted);
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  font-size: var(--size-badge);
  box-shadow: var(--shadow-chip);
}
.provenance__dot { width: 7px; height: 7px; border-radius: var(--radius-circle); background: var(--accent); color: var(--on-accent); box-shadow: var(--ring-dot); flex-shrink: 0; }
.provenance b { color: var(--accent); }
.lede h1 { margin: 18px 0 0; font-size: clamp(30px, 3.4vw, 48px); color: var(--text); }
.lede .brandword { color: var(--text); }
.lede__desc { max-width: 660px; margin: 18px auto 0; font-size: var(--size-body); line-height: 1.7; color: var(--text-muted); }
.lede__desc strong { color: var(--text); }
.devrow { display: flex; justify-content: center; align-items: center; flex-wrap: wrap; gap: 8px 26px; margin: 16px 0 0; padding: 0; list-style: none; }
.devrow a { display: inline-flex; align-items: center; gap: 7px; font-size: var(--size-device); color: var(--text-muted); transition: color var(--duration-fast); }
.devrow a:hover { color: var(--accent-dark); text-decoration: none; }
.devrow svg { width: 18px; height: 18px; flex-shrink: 0; fill: none; stroke: currentColor; stroke-width: 1.5; stroke-linecap: round; stroke-linejoin: round; }
.storepill { display: inline-flex; align-items: center; gap: 6px; min-height: 24px; padding: 1px 10px; border: 1px solid var(--border); border-radius: var(--radius-pill); background: var(--bg-panel); font-size: var(--size-label); color: var(--text-muted); }
.storepill svg { width: 11px; height: 11px; fill: currentColor; stroke: none; }
.flowpair { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 32px; max-width: 1080px; margin: 50px auto 0; }
.flowcard {
  position: relative;
  min-width: 0;
  background: linear-gradient(180deg, var(--bg-panel) 58%, var(--bg) 100%);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
  padding: 20px 24px 22px;
  text-align: center;
}
.flowcard__tag { display: inline-flex; align-items: center; min-height: 24px; padding: 2px 12px; border-radius: var(--radius-pill); font-size: var(--size-xs); font-weight: var(--weight-medium); letter-spacing: var(--tracking-label); }
.flowcard__tag--g { background: var(--accent-tint); color: var(--accent-hover); }
.flowcard__tag--n { background: var(--bg-panel-2); color: var(--text); }
.flowcard__art { width: 100%; max-width: 440px; height: auto; margin: 8px auto 0; }
.flowcard h2 { margin: 6px 0 0; font-weight: var(--weight-medium); font-size: var(--size-h3); line-height: 1.3; letter-spacing: -.01em; color: var(--text); }
.flowcard p { max-width: 410px; margin: 6px auto 0; font-size: var(--size-sm); line-height: 1.7; color: var(--text-muted); }
.flowcard__go { display: inline-block; margin-top: 8px; font-size: var(--size-sm); color: var(--accent-dark); }
.wire { fill: none; stroke: var(--accent-dark); stroke-width: 1.5; stroke-dasharray: 4 5; stroke-linecap: round; }
.disc-g { fill: var(--accent-tint); }
.disc-t { fill: var(--teal-tint); }
.disc-solid { fill: var(--accent); }
.halo { fill: var(--accent); opacity: .12; }
.ln-g { fill: none; stroke: var(--accent); stroke-width: 1.6; stroke-linecap: round; stroke-linejoin: round; }
.ln-t { fill: none; stroke: var(--accent-dark); stroke-width: 1.4; stroke-linecap: round; stroke-linejoin: round; }
.ln-w { fill: none; stroke: var(--on-accent); stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.fill-g { fill: var(--accent); }
.fill-w { fill: var(--on-accent); }
.cap { fill: var(--bg-panel); stroke: var(--accent-dark); stroke-width: 1; }
.cap--err { stroke: var(--error); }
.cap-txt { font-family: var(--font-mono); font-size: var(--size-art-code); letter-spacing: .02em; fill: var(--accent-dark); }
.cap-txt--rule { fill: var(--text); font-size: var(--size-art-rule); letter-spacing: 0; }
.cap-txt--err { fill: var(--error); }
.art-label { font-family: var(--font-body); font-size: var(--size-art); fill: var(--text-muted); }
.factband { margin-top: 28px; background: var(--band-bg); color: var(--text); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.factband__list { display: flex; justify-content: center; align-items: center; flex-wrap: wrap; max-width: 1320px; margin: 0 auto; padding: 0 var(--gutter); min-height: 44px; list-style: none; font-family: var(--font-mono); font-size: var(--size-label); color: var(--text); }
.factband__list li { display: flex; align-items: center; flex-wrap: wrap; gap: 9px; padding-block: 6px; min-width: 0; }
.factband__list li + li::before { content: ""; width: 4px; height: 4px; flex-shrink: 0; border-radius: var(--radius-circle); background: var(--border); margin-inline: 26px; }
.factband__k { color: var(--text-muted); }
.factband__v { color: var(--accent-dark); overflow-wrap: anywhere; }
.nextup { padding-top: 40px; padding-bottom: 120px; }
.nextup__eyebrow { display: block; font-size: var(--size-label); letter-spacing: .08em; color: var(--accent-dark); font-family: var(--font-mono); text-align: center; }
.nextup h2 { margin: 8px 0 0; text-align: center; font-size: var(--size-h2); color: var(--text); }

/* 默认可见；只有脚本成功启动后才启用淡入。 */
.reveal { opacity: 1; transform: none; }
.reveal-ready .reveal:not(.shown) { opacity: 0; transform: translateY(12px); }
.reveal-ready .reveal { transition: opacity var(--duration-reveal) ease, transform var(--duration-reveal) ease; }
.reveal-ready .reveal.shown { opacity: 1; transform: none; }

.site-footer { padding-top: 64px; padding-bottom: 28px; background: var(--bg-panel-2); color: var(--text); border-top: 1px solid var(--border); }
.footer-grid { display: grid; grid-template-columns: 1.5fr 1fr 1.2fr 1fr; gap: 36px; }
.footer-brand p { margin: 20px 0 0; font-size: var(--size-sm); line-height: 1.8; color: var(--text-muted); max-width: 340px; }
.footer-title { font-size: var(--size-sm); font-weight: var(--weight-medium); margin: 0 0 14px; }
.footer-links { list-style: none; margin: 0; padding: 0; }
.footer-links li { margin-bottom: 6px; }
.footer-links a { display: inline-block; padding-block: 4px; font-size: var(--size-sm); }
.footer-bottom { margin-top: 40px; padding-top: 20px; border-top: 1px solid var(--border); display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px 28px; color: var(--text-muted); font-size: var(--size-xs); }
.footer-bottom p { margin: 0; }

@media (max-width: 1279px) {
  .navline { display: none; }
  .header-tools { margin-left: auto; }
  .menu-toggle { display: inline-flex; }
  .langpick { border-left: 0; padding-left: 0; }
}
@media (max-width: 860px) {
  :root { --gutter: 20px; }
  .flowpair { grid-template-columns: minmax(0, 1fr); gap: 20px; max-width: 540px; }
  .factband__list li + li::before { margin-inline: 14px; }
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .card-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 768px) {
  :root { --size-h1: clamp(24px, 4vw, 30px); --size-h2: 25px; }
  .lede h1 { font-size: clamp(24px, 4vw, 30px); line-height: 1.25; }
}
@media (max-width: 640px) {
  :root { --gutter: 16px; --section-space: 120px; }
  .topbar__in { gap: 10px; }
  .brandmark { gap: 7px; }
  .brandmark__name { font-size: var(--size-xs); }
  .brandmark__logo, .brandmark__tile { width: 28px; height: 28px; }
  .header-tools { gap: 6px; margin-left: auto; }
  .langpick { font-size: var(--size-xs); gap: 4px; }
  .grid-two, .card-grid, .footer-grid { grid-template-columns: minmax(0, 1fr); }
  .card, .panel { padding: 22px; }
  .flowcard { padding-inline: 16px; }
  .factband__list { gap: 4px 16px; padding-block: 10px; }
  .factband__list li + li::before { display: none; }
  .tilt, [data-tilt] { transform: none !important; }
  .prose h2 { margin-top: 48px; }
}
@media (max-width: 560px) {
  .ctas { flex-direction: column; align-items: stretch; max-width: 300px; margin-inline: auto; }
  .lede__desc { font-size: var(--size-button); }
  .devrow { gap: 10px 16px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal-ready .reveal:not(.shown) { opacity: 1; transform: none; }
  .reveal-ready .reveal, .btn, .navline__list a, .devrow a { transition: none; }
  .halo, .provenance__dot { animation: none; }
}