:root {
  --bg: #fbfbfe;
  --bg-panel: #f4f5f9;
  --bg-panel-2: #eceef4;
  --border: #e3e5ec;
  --accent: #ef5b45;
  --accent-dark: #c4402d;
  --text: #16171d;
  --text-muted: #5d6070;
  --success: #1f9a74;
  --warn: #b07a1c;
  --error: #c22f4b;
  --surface: #ffffff;
  --on-accent: #ffffff;
  --text-faint: #8a8d9b;
  --rule: #c6c9d3;
  --dot: #d5d8e1;
  --accent-wash: #fdf1ee;
  --accent-edge: #f5c6bd;
  --mask: #000000;
  --clear: transparent;
  --shadow-hair: rgba(22, 23, 29, .05);
  --shadow-soft: rgba(22, 23, 29, .10);
  --veil: rgba(22, 23, 29, .20);

  --font-display: "Inter", "Noto Sans SC", -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans", "Apple SD Gothic Neo", "Microsoft YaHei", sans-serif;
  --font-body: "Inter", "Noto Sans SC", -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans", "Apple SD Gothic Neo", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;

  --weight-normal: 400;
  --weight-medium: 500;
  --r-xs: 4px;
  --r: 6px;
  --r-mark: 8px;
  --r-shot: 10px;
  --r-pill: 999px;
  --r-circle: 50%;
  --frame: 1120px;
  --header-frame: 1280px;
  --gutter: 24px;
  --reading-frame: 780px;
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;
  --space-7: 48px;
  --space-8: 64px;
  --space-9: 88px;
  --size-body: 15px;
  --size-small: 13px;
  --size-h1: clamp(34px, 3.4vw, 48px);
  --size-h2: 28px;
  --size-h3: 20px;
  --leading-body: 1.6;
  --leading-title: 1.1;
  --tracking-title: -.025em;
  --tracking-cjk: -.02em;
  --motion-fast: 160ms;
  --motion-reveal: 480ms;
  --motion-horizon: 10s;
  --focus-ring: 2px solid var(--accent-dark);
  --shadow-rig: 0 1px 2px var(--shadow-hair), 0 18px 40px -28px var(--shadow-soft);
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
html.nav-open { overflow: hidden; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: var(--size-body);
  line-height: var(--leading-body);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
button, input, select, textarea { font: inherit; }
button { cursor: pointer; }
a { color: inherit; text-underline-offset: .2em; }
img { max-width: 100%; }
svg { display: block; flex-shrink: 0; }
button svg, a svg { pointer-events: none; }
[hidden] { display: none !important; }
:focus-visible { outline: var(--focus-ring); outline-offset: 4px; }
h1, h2, h3 {
  font-family: var(--font-display);
  font-weight: var(--weight-normal);
  text-wrap: balance;
  overflow-wrap: break-word;
}
h1 { font-size: var(--size-h1); line-height: var(--leading-title); letter-spacing: var(--tracking-cjk); }
h2 { font-size: var(--size-h2); line-height: 1.25; letter-spacing: var(--tracking-cjk); }
h3 { font-size: var(--size-h3); line-height: 1.4; letter-spacing: -.01em; }
strong, b { font-weight: var(--weight-medium); }
code, pre { font-family: var(--font-mono); }
code { overflow-wrap: anywhere; }
pre {
  max-width: 100%;
  min-width: 0;
  overflow-x: auto;
  padding: var(--space-5);
  border: 1px solid var(--border);
  border-radius: var(--r);
  background: var(--bg-panel);
  color: var(--text);
  font-size: var(--size-small);
  overscroll-behavior-inline: contain;
}
pre code { white-space: pre; overflow-wrap: normal; word-break: normal; }
blockquote { margin-inline: 0; }
:where(section, article, aside, div, nav) { min-width: 0; }
[id] { scroll-margin-top: 24px; }
.nowrap { white-space: nowrap; }
.text-muted { color: var(--text-muted); }
.mono { font-family: var(--font-mono); }
.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: absolute;
  z-index: 100;
  top: 8px;
  left: var(--gutter);
  padding: var(--space-3);
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--r);
  opacity: 0;
  pointer-events: none;
}
.skip-link:focus { opacity: 1; pointer-events: auto; }

.sheet { position: relative; overflow-x: clip; }
.sheet__guides {
  position: absolute;
  inset: 0;
  width: min(var(--frame), calc(100% - var(--gutter) * 2));
  margin-inline: auto;
  border-inline: 1px dashed var(--border);
  pointer-events: none;
  z-index: 0;
}
.frame, .wrap {
  position: relative;
  width: 100%;
  max-width: calc(var(--frame) + var(--gutter) * 2);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.reading { max-width: calc(var(--reading-frame) + var(--gutter) * 2); }
.section {
  position: relative;
  padding-top: var(--space-8);
  padding-bottom: var(--space-8);
  overflow-x: clip;
}
.band {
  position: relative;
  z-index: 1;
  background: var(--bg-panel);
  color: var(--text);
  border-top: 1px solid var(--border);
  padding-top: var(--space-8);
  padding-bottom: var(--space-9);
}
.band__kicker {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--text-muted);
}
.band__title { margin: 10px 0 0; }
.band__lead { margin: 12px 0 0; max-width: 640px; color: var(--text-muted); }
.prose { min-width: 0; }
.prose p, .prose li { line-height: 1.85; }
.prose h2 { margin-top: var(--space-8); margin-bottom: var(--space-5); }
.prose h3 { margin-top: var(--space-6); }
.prose :where(ul, ol) { padding-left: 1.5em; }
.prose a:not(.btn):not(.store-button) { color: var(--accent-dark); }
.prose > :first-child { margin-top: 0; }
.grid { display: grid; gap: var(--space-5); }
.grid--two { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--three { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid > *, .flex > * { min-width: 0; }
.panel, .card {
  padding: var(--space-5);
  border: 1px solid var(--border);
  border-radius: var(--r);
  background: var(--surface);
  color: var(--text);
}
.card h3, .panel h3 { margin-top: 0; }
.card p:last-child, .panel p:last-child { margin-bottom: 0; }
.card__meta { font-family: var(--font-mono); font-size: 12px; color: var(--text-muted); }
.card--link { display: block; text-decoration: none; }
.card--link:hover { border-color: var(--rule); }
.actions {
  margin-top: 26px;
  display: flex;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
}
.btn {
  display: inline-flex;
  justify-content: center;
  align-items: center;
  gap: 9px;
  min-height: 44px;
  padding: 9px 18px;
  max-width: 100%;
  border: 1px solid var(--clear);
  border-radius: var(--r);
  font-family: var(--font-body);
  font-size: 15px;
  font-weight: var(--weight-medium);
  line-height: 1.6;
  text-align: center;
  text-decoration: none;
  transition: background-color var(--motion-fast), border-color var(--motion-fast);
}
.btn svg { width: 17px; height: 17px; }
.btn--primary { background: var(--accent); color: var(--on-accent); }
.btn--primary:hover, .btn--primary.is-hover { background: var(--accent-dark); color: var(--on-accent); }
.btn--ghost { background: var(--surface); color: var(--text); border-color: var(--border); }
.btn--ghost:hover, .btn--ghost.is-hover { background: var(--bg-panel); color: var(--text); }
.btn--ghost svg { width: 15px; height: 15px; color: var(--text-muted); }
.btn:disabled, .btn[aria-disabled="true"] {
  background: var(--bg-panel-2);
  color: var(--text-muted);
  border-color: var(--border);
  cursor: not-allowed;
}
.btn.is-focus { outline: var(--focus-ring); outline-offset: 4px; }

.factline {
  position: relative;
  z-index: 2;
  height: 30px;
  background: var(--bg-panel);
  color: var(--text-muted);
  border-bottom: 1px solid var(--border);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .02em;
}
.factline .frame {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  white-space: nowrap;
  overflow: hidden;
}
.factline__list { display: flex; align-items: center; gap: 10px; flex-shrink: 0; }
.factline__sep, .factline__host { color: var(--text-faint); }

.masthead { position: relative; z-index: 40; }
.masthead__row {
  height: 60px;
  display: flex;
  align-items: center;
  gap: 24px;
}
.header-frame {
  width: 100%;
  max-width: min(100%, calc(var(--header-frame) + var(--gutter) * 2));
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-size: 15px;
  font-weight: var(--weight-medium);
  letter-spacing: -.005em;
  color: var(--text);
  white-space: nowrap;
  flex-shrink: 0;
}
.brand__mark {
  display: block;
  width: 28px;
  height: 28px;
  flex-shrink: 0;
  border-radius: var(--r-mark);
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--border);
}
.brand__mark--placeholder { box-shadow: inset 0 0 0 4px var(--bg-panel); }
.mainnav { margin-left: auto; display: flex; align-items: center; min-width: 0; }
.mainnav__list {
  display: flex;
  align-items: center;
  list-style: none;
  margin: 0;
  padding: 0;
  gap: 2px;
}
.mainnav__link {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  height: 32px;
  padding: 0 12px;
  border: 1px solid var(--clear);
  border-radius: var(--r-pill);
  font-size: 14px;
  color: var(--text-muted);
  text-decoration: none;
  white-space: nowrap;
}
.mainnav__link:hover { color: var(--text); }
.mainnav__link[aria-current="page"] {
  color: var(--text);
  background: var(--bg-panel);
  border-color: var(--border);
}
.mainnav__link[aria-current="page"]::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: var(--r-circle);
  background: var(--accent);
  flex-shrink: 0;
}
.header-tools { display: flex; align-items: center; gap: 8px; flex-shrink: 0; }
.language { position: relative; }
.lang {
  padding: 0 0 0 16px;
  height: 22px;
  border: 0;
  border-left: 1px solid var(--border);
  background: none;
  color: var(--text-muted);
  font-family: var(--font-body);
  font-size: 13.5px;
  white-space: nowrap;
}
.lang:hover { color: var(--text); }
.lang__short { display: none; }
.language__menu {
  position: absolute;
  top: calc(100% + 14px);
  right: 0;
  width: 180px;
  padding: 6px;
  border: 1px solid var(--border);
  border-radius: var(--r);
  background: var(--surface);
  color: var(--text);
  z-index: 3;
}
.language__menu a {
  display: flex;
  align-items: center;
  min-height: 44px;
  padding: 10px 12px;
  width: 100%;
  text-decoration: none;
  border-radius: var(--r-xs);
}
.language__menu a:hover, .language__menu a[aria-current="true"] {
  background: var(--bg-panel);
  color: var(--text);
}
.menu-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  min-width: 44px;
  min-height: 44px;
  border: 1px solid var(--border);
  border-radius: var(--r);
  background: var(--surface);
  color: var(--text);
}
.menu-toggle svg { width: 20px; height: 20px; }
.nav-veil {
  position: fixed;
  inset: 90px 0 0;
  background: var(--veil);
  color: var(--text);
  z-index: 0;
  border: 0;
  width: 100%;
}
.mobile-drawer {
  position: absolute;
  top: 100%;
  inset-inline: 0;
  padding: 16px var(--gutter) 24px;
  max-height: calc(100dvh - 90px);
  overflow-y: auto;
  overscroll-behavior: contain;
  background: var(--surface);
  color: var(--text);
  border-block: 1px solid var(--border);
  z-index: 2;
}
.mobile-drawer ul { padding: 0; margin: 0; list-style: none; }
.mobile-drawer a {
  display: flex;
  align-items: center;
  gap: 8px;
  width: 100%;
  min-height: 44px;
  padding: 10px 16px;
  text-decoration: none;
  border-radius: var(--r);
  color: var(--text-muted);
}
.mobile-drawer a:hover, .mobile-drawer a[aria-current] {
  background: var(--bg-panel);
  color: var(--text);
}
.mobile-drawer a[aria-current="page"]::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: var(--r-circle);
  background: var(--accent);
  flex-shrink: 0;
}
.mobile-drawer__label {
  margin: 16px 16px 8px;
  padding-top: 16px;
  border-top: 1px dashed var(--border);
  font-size: 12px;
  color: var(--text-muted);
}

.hero {
  position: relative;
  padding-top: 40px;
  padding-bottom: 28px;
  text-align: center;
  isolation: isolate;
  overflow-x: clip;
}
.hero__inner { position: relative; z-index: 1; }
.hero__title {
  margin: 22px 0 0;
  font-family: var(--font-display);
  font-weight: var(--weight-normal);
  font-size: clamp(30px, 3.4vw, 48px);
  line-height: 1.1;
  letter-spacing: var(--tracking-title);
  color: var(--text);
}
.hero__title > span { display: block; }
.hero__facts {
  margin: 20px auto 0;
  max-width: 680px;
  font-size: 15px;
  line-height: 1.6;
  color: var(--text-muted);
}
.hero__facts strong { color: var(--text); }
.horizon {
  position: absolute;
  inset-inline: 0;
  bottom: 0;
  height: 500px;
  overflow: hidden;
  pointer-events: none;
  z-index: 0;
  -webkit-mask-image: linear-gradient(to top, var(--mask) 0%, var(--mask) 30%, var(--clear) 92%);
  mask-image: linear-gradient(to top, var(--mask) 0%, var(--mask) 30%, var(--clear) 92%);
}
.horizon__plane {
  position: absolute;
  left: -60%;
  right: -60%;
  bottom: -10%;
  height: 150%;
  transform: perspective(560px) rotateX(63deg);
  transform-origin: 50% 100%;
  overflow: hidden;
}
.horizon__grid {
  position: absolute;
  inset: -56px 0 0;
  background-image: linear-gradient(var(--border) 1px, var(--clear) 1px), linear-gradient(90deg, var(--border) 1px, var(--clear) 1px);
  background-size: 56px 56px;
  animation: horizon-pan var(--motion-horizon) linear infinite;
}
@keyframes horizon-pan { from { transform: translateY(0); } to { transform: translateY(56px); } }

.site-footer {
  position: relative;
  z-index: 1;
  padding-top: var(--space-8);
  padding-bottom: var(--space-6);
  border-top: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
}
.footer-grid { display: grid; grid-template-columns: 1.3fr 1fr 1.3fr 1fr; gap: var(--space-6); }
.footer-grid > * { min-width: 0; }
.footer-brand .brand { white-space: normal; }
.footer-brand p { max-width: 280px; color: var(--text-muted); font-size: 13px; }
.footer-column h2 { margin: 0 0 12px; font-size: 14px; }
.footer-column ul { margin: 0; padding: 0; list-style: none; }
.footer-column a {
  display: inline-block;
  padding-top: 5px;
  padding-bottom: 5px;
  color: var(--text-muted);
  text-decoration: none;
  font-size: 13px;
  overflow-wrap: anywhere;
}
.footer-column a:hover { color: var(--text); text-decoration: underline; }
.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 12px;
  margin-top: var(--space-7);
  padding-top: var(--space-5);
  border-top: 1px dashed var(--border);
  font-size: 12px;
  color: var(--text-muted);
}
.footer-bottom p { margin: 0; }

.reveal { opacity: 1; transform: none; }
html.reveal-ready .reveal:not(.shown) { opacity: 0; transform: translateY(12px); }
html.reveal-ready .reveal {
  transition: opacity var(--motion-reveal) ease, transform var(--motion-reveal) ease;
}
html.reveal-ready .reveal.shown { opacity: 1; transform: none; }

@media (max-width: 1279px) {
  .masthead--live .mainnav { display: none; }
  .masthead--live .header-tools { margin-left: auto; }
  .masthead--live .menu-toggle { display: inline-flex; }
}
@media (max-width: 960px) {
  .mainnav__link { padding-inline: 9px; font-size: 13.5px; }
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid--three { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 768px) {
  h1 { font-size: clamp(24px, 7.2vw, 30px); }
  .hero__title { font-size: clamp(24px, 7.2vw, 30px); }
}
@media (max-width: 720px) {
  :root { --gutter: 16px; }
  .factline__host { display: none; }
  .hero { padding-top: 28px; }
  .hero__facts { font-size: 14px; }
  .band__title { font-size: 22px; }
  .masthead:not(.masthead--live) .masthead__row {
    height: auto;
    flex-wrap: wrap;
    gap: 8px 16px;
    padding-top: 12px;
    padding-bottom: 12px;
  }
  .masthead:not(.masthead--live) .mainnav { margin-left: 0; width: 100%; overflow-x: auto; order: 3; }
  .masthead:not(.masthead--live) .header-tools { margin-left: auto; }
}
@media (max-width: 640px) {
  .grid--two, .grid--three { grid-template-columns: minmax(0, 1fr); }
  .footer-grid { grid-template-columns: minmax(0, 1fr); gap: 24px; }
  .brand { font-size: 13px; gap: 8px; }
  .masthead__row { gap: 8px; }
  .lang { padding-left: 10px; }
  .lang__full { display: none; }
  .lang__short { display: inline; }
  .tilt, .decorative-tilt { transform: none; }
  .section, .band { padding-top: 40px; padding-bottom: 48px; }
  .prose h2 { font-size: 24px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .horizon__grid { animation: none; }
  html.reveal-ready .reveal:not(.shown) { opacity: 1; transform: none; }
  html.reveal-ready .reveal, .btn { transition: none; }
}