:root {
  --c-bg: #FFFFFF;
  --c-panel: #F3F3F2;
  --c-block: #151614;
  --c-border: #E4E4E2;
  --c-accent: #C8F171;
  --c-accent-dark: #4E7A1C;
  --c-text: #151614;
  --c-muted: #5E615E;
  --c-success: #2E9E5B;
  --c-warn: #D98A00;
  --c-error: #D63B2F;
  --c-on-dark: #FFFFFF;
  --c-on-dark-80: rgba(255, 255, 255, .80);
  --c-on-dark-68: rgba(255, 255, 255, .68);
  --c-on-dark-52: rgba(255, 255, 255, .52);
  --c-on-dark-28: rgba(255, 255, 255, .28);
  --c-on-dark-16: rgba(255, 255, 255, .16);
  --c-on-dark-10: rgba(255, 255, 255, .10);
  --c-on-dark-06: rgba(255, 255, 255, .06);
  --c-accent-glow: rgba(200, 241, 113, .17);
  --c-accent-tint: rgba(200, 241, 113, .34);
  --c-skeleton: #E9E9E6;
  --c-control-line: #C9CAC5;
  --c-veil: rgba(21, 22, 20, .35);
  --c-clear: transparent;
  --shadow-float: 0 1px 2px rgba(21, 22, 20, .24), 0 30px 60px -20px rgba(0, 0, 0, .62);
  --shadow-knob: 0 1px 2px rgba(21, 22, 20, .28);
  --shadow-seg: 0 1px 2px rgba(21, 22, 20, .18);
  --shadow-cta: 0 0 0 1px rgba(200, 241, 113, .28), 0 14px 32px -12px rgba(200, 241, 113, .6);
  --shadow-fab: 0 1px 2px rgba(21, 22, 20, .14), 0 14px 30px -10px rgba(21, 22, 20, .32);
  --shadow-card: 0 1px 2px rgba(21, 22, 20, .04), 0 16px 32px -20px rgba(21, 22, 20, .20);
  --ring-white: 0 0 0 6px var(--c-bg);
  --r-hero: 32px;
  --r-panel: 28px;
  --r-card: 16px;
  --r-row: 10px;
  --r-small: 6px;
  --r-pill: 999px;
  --r-circle: 50%;
  --f-display: 'Inter', 'Noto Sans SC', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', system-ui, sans-serif;
  --f-body: 'Inter', 'Noto Sans SC', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', system-ui, sans-serif;
  --f-mono: 'JetBrains Mono', ui-monospace, 'SFMono-Regular', Menlo, Consolas, monospace;
  --weight-normal: 400;
  --weight-medium: 500;
  --weight-semibold: 600;
  --weight-bold: 700;
  --weight-display: 800;
  --size-body: 16px;
  --size-small: 14px;
  --size-label: 12px;
  --size-h1: clamp(34px, 3.4vw, 48px);
  --size-h2: clamp(26px, 2.7vw, 36px);
  --size-h3: 22px;
  --wrap: 1248px;
  --reading: 800px;
  --gutter: 24px;
  --hero-pad: 72px;
  --header-height: 72px;
  --section-space: 88px;
  --ease: .18s ease;
  --reveal-time: .55s;
}
*, *::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(--c-bg);
  color: var(--c-text);
  font-family: var(--f-body);
  font-size: var(--size-body);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}
[hidden] { display: none !important; }
img, svg, video { max-width: 100%; }
img { height: auto; }
button, input, select, textarea { font: inherit; }
button { cursor: pointer; }
button, a { -webkit-tap-highlight-color: var(--c-clear); }
a { color: inherit; text-underline-offset: .2em; }
a:hover { text-decoration-thickness: 2px; }
a:focus-visible, button:focus-visible, summary:focus-visible, [tabindex]:focus-visible {
  outline: 2px solid var(--c-accent-dark);
  outline-offset: 3px;
}
.hero a:focus-visible { outline-color: var(--c-accent); }
h1, h2, h3 {
  font-family: var(--f-display);
  font-weight: var(--weight-display);
  letter-spacing: -.02em;
  line-height: 1.25;
  text-wrap: balance;
  margin: 0 0 20px;
}
h1 { font-size: var(--size-h1); line-height: 1.16; }
h2 { font-size: var(--size-h2); }
h3 { font-size: var(--size-h3); }
p { margin: 0 0 1.25em; }
strong { font-weight: var(--weight-bold); }
small { font-size: var(--size-label); }
code, pre, kbd { font-family: var(--f-mono); }
code { overflow-wrap: anywhere; }
pre {
  max-width: 100%;
  min-width: 0;
  overflow-x: auto;
  padding: 24px;
  border-radius: var(--r-card);
  background: var(--c-block);
  color: var(--c-on-dark-80);
  font-size: var(--size-small);
  tab-size: 2;
}
pre code { white-space: pre; overflow-wrap: normal; word-break: normal; }
hr { border: 0; border-top: 1px solid var(--c-border); margin: 32px 0; }
.wrap {
  width: 100%;
  max-width: calc(var(--wrap) + var(--gutter) * 2);
  padding-inline: var(--gutter);
  margin-inline: auto;
}
.reading { max-width: calc(var(--reading) + var(--gutter) * 2); }
.section { padding-top: var(--section-space); padding-bottom: var(--section-space); }
.grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 24px; }
.grid > *, .hero__inner > *, .footer-grid > *, .flow-panel > * { min-width: 0; }
.stack > * + * { margin-top: 24px; }
.muted { color: var(--c-muted); }
.accent { color: var(--c-accent-dark); }
.mono { font-family: var(--f-mono); }
.keep { white-space: nowrap; }
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}
.panel {
  padding: 40px;
  background: var(--c-panel);
  color: var(--c-text);
  border: 1px solid var(--c-border);
  border-radius: var(--r-panel);
}
.surface-card {
  padding: 28px;
  background: var(--c-bg);
  color: var(--c-text);
  border: 1px solid var(--c-border);
  border-radius: var(--r-card);
  box-shadow: var(--shadow-card);
}
.decorated { position: relative; overflow-x: clip; }
.prose { min-width: 0; line-height: 1.85; }
.prose h2 { margin-top: 64px; }
.prose h3 { margin-top: 36px; }
.prose li + li { margin-top: 8px; }
.prose a { color: var(--c-accent-dark); }
.prose :not(pre) > code {
  background: var(--c-panel);
  color: var(--c-text);
  border-radius: var(--r-small);
  padding: .12em .3em;
}
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 52px;
  padding: 12px 26px;
  border: 1px solid var(--c-clear);
  border-radius: var(--r-pill);
  font-family: var(--f-body);
  font-size: var(--size-body);
  font-weight: var(--weight-bold);
  line-height: 1.5;
  text-align: center;
  text-decoration: none;
  transition: transform var(--ease), background-color var(--ease), border-color var(--ease);
}
.btn svg { width: 18px; height: 18px; flex-shrink: 0; }
.btn:hover { transform: translateY(-1px); }
.btn:active, .btn.is-active { transform: translateY(1px); }
.btn--primary { background: var(--c-accent); color: var(--c-text); box-shadow: var(--shadow-cta); }
.btn--secondary { background: var(--c-bg); color: var(--c-text); border-color: var(--c-border); }
.btn--secondary:hover { background: var(--c-panel); }
.btn--ghost { background: var(--c-clear); color: var(--c-on-dark); border-color: var(--c-on-dark-28); }
.btn--ghost:hover { background: var(--c-on-dark-06); border-color: var(--c-on-dark-52); }
.btn:disabled, .btn[aria-disabled="true"] {
  background: var(--c-panel);
  color: var(--c-muted);
  border-color: var(--c-border);
  box-shadow: none;
  cursor: not-allowed;
  transform: none;
}
.btn.is-focus { outline: 2px solid var(--c-accent-dark); outline-offset: 3px; }
.actions { display: flex; flex-wrap: wrap; align-items: center; gap: 12px; margin-top: 34px; }
.topbar { position: relative; height: var(--header-height); z-index: 100; background: var(--c-bg); color: var(--c-text); }
.topbar__inner {
  position: relative;
  width: 100%;
  max-width: min(100%, calc(1280px + var(--gutter) * 2));
  padding-inline: var(--gutter);
  height: 100%;
  margin-inline: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
}
.brand { display: inline-flex; align-items: center; gap: 12px; text-decoration: none; flex-shrink: 0; }
.brand__mark { display: block; width: 34px; height: 34px; flex-shrink: 0; }
.brand__name { font-family: var(--f-display); font-weight: var(--weight-display); font-size: 18px; letter-spacing: -.02em; }
.desktop-nav { margin-left: auto; min-width: 0; }
.nav {
  display: flex;
  align-items: center;
  list-style: none;
  margin: 0;
  padding: 0;
  gap: 4px;
}
.nav__link {
  display: block;
  padding: 8px 16px;
  border-radius: var(--r-pill);
  font-size: 15px;
  font-weight: var(--weight-medium);
  color: var(--c-muted);
  text-decoration: none;
  white-space: nowrap;
  transition: color var(--ease), background-color var(--ease);
}
.nav__link:hover { color: var(--c-text); }
.nav__link[aria-current="page"] {
  background: var(--c-panel);
  color: var(--c-text);
  font-weight: var(--weight-bold);
  box-shadow: inset 0 0 0 1px var(--c-border);
}
.topbar__tools { display: flex; align-items: center; gap: 12px; flex-shrink: 0; }
.language-picker { position: relative; }
.lang {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  height: 38px;
  padding: 0 14px;
  border: 1px solid var(--c-border);
  border-radius: var(--r-pill);
  background: var(--c-bg);
  color: var(--c-text);
  font-size: var(--size-small);
  font-weight: var(--weight-medium);
  text-decoration: none;
}
.lang svg { width: 16px; height: 16px; flex-shrink: 0; color: var(--c-muted); }
.lang__caret { color: var(--c-muted); font-size: 11px; }
.lang__short { display: none; }
.language-menu {
  position: absolute;
  right: 0;
  top: calc(100% + 12px);
  width: 200px;
  padding: 8px;
  margin: 0;
  list-style: none;
  background: var(--c-bg);
  color: var(--c-text);
  border: 1px solid var(--c-border);
  border-radius: var(--r-card);
  box-shadow: var(--shadow-card);
  z-index: 5;
}
.language-menu a { display: block; padding: 10px 12px; min-height: 44px; text-decoration: none; border-radius: var(--r-row); }
.language-menu a:hover, .language-menu a[aria-current="true"] { background: var(--c-panel); color: var(--c-text); }
.menu-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  min-width: 44px;
  min-height: 44px;
  padding: 10px;
  border: 1px solid var(--c-border);
  border-radius: var(--r-pill);
  background: var(--c-bg);
  color: var(--c-text);
}
.menu-toggle svg { width: 20px; height: 20px; }
.mobile-drawer {
  position: absolute;
  inset: var(--header-height) 0 auto;
  padding: 16px var(--gutter) 24px;
  max-height: calc(100dvh - var(--header-height));
  overflow-y: auto;
  overscroll-behavior: contain;
  background: var(--c-bg);
  color: var(--c-text);
  border-bottom: 1px solid var(--c-border);
  z-index: 3;
}
.mobile-drawer ul { padding: 0; margin: 0; list-style: none; }
.mobile-drawer a {
  display: flex;
  align-items: center;
  width: 100%;
  min-height: 48px;
  padding: 12px 16px;
  border-radius: var(--r-row);
  text-decoration: none;
}
.mobile-drawer a:hover, .mobile-drawer a[aria-current] { background: var(--c-panel); color: var(--c-text); }
.mobile-drawer__languages { border-top: 1px solid var(--c-border); margin-top: 16px !important; padding-top: 16px !important; }
.nav-veil { position: fixed; inset: var(--header-height) 0 0; border: 0; background: var(--c-veil); color: var(--c-text); z-index: 1; }
.site-footer {
  background: var(--c-panel);
  color: var(--c-text);
  border-top: 1px solid var(--c-border);
  padding-top: 64px;
  padding-bottom: 104px;
}
.footer-grid { display: grid; grid-template-columns: 1.2fr .8fr 1.3fr .7fr; gap: 40px; }
.footer-grid h2 { font-size: var(--size-small); letter-spacing: 0; margin-bottom: 18px; }
.footer-grid p { color: var(--c-muted); font-size: var(--size-small); margin-top: 20px; max-width: 26em; }
.footer-links { list-style: none; padding: 0; margin: 0; display: grid; gap: 10px; }
.footer-links a { color: var(--c-muted); text-decoration: none; font-size: var(--size-small); }
.footer-links a:hover { color: var(--c-text); text-decoration: underline; }
.footer-bottom { display: flex; flex-wrap: wrap; gap: 20px; margin-top: 48px; padding-top: 24px; border-top: 1px solid var(--c-border); color: var(--c-muted); font-size: var(--size-label); }
.footer-bottom p { margin: 0 auto 0 0; }
.reveal { opacity: 1; transform: none; }
.reveal.is-waiting { opacity: 0; transform: translateY(18px); transition: opacity var(--reveal-time) ease, transform var(--reveal-time) ease; }
.reveal.shown { opacity: 1; transform: none; }
@media (max-width: 1279px) {
  .desktop-nav { display: none; }
  .menu-toggle { display: inline-flex; }
  .topbar__tools { margin-left: auto; }
}
@media (min-width: 1280px) {
  .mobile-drawer, .nav-veil { display: none !important; }
}
@media (max-width: 1180px) {
  :root { --hero-pad: 48px; }
}
@media (max-width: 768px) {
  :root { --size-h1: clamp(24px, 4vw, 30px); --section-space: 56px; }
  .grid { grid-template-columns: minmax(0, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 32px; }
  .panel { padding: 28px; }
}
@media (max-width: 640px) {
  :root { --gutter: 16px; --hero-pad: 24px; }
  .topbar__inner { gap: 10px; }
  .topbar__tools { gap: 6px; margin-left: auto; }
  .brand { gap: 8px; }
  .brand__name { font-size: 16px; }
  .topbar .brand { min-width: 0; flex-shrink: 1; }
  .topbar .brand__name { min-width: 0; overflow-wrap: anywhere; line-height: 1.25; }
  .lang { padding-inline: 10px; }
  .lang__full { display: none; }
  .lang__short { display: inline; }
  .lang svg { display: none; }
  .panel, .surface-card { padding: 22px; }
  .tilt, .card--sub, .card--proxy, .card--core { transform: none; }
  .footer-grid { grid-template-columns: minmax(0, 1fr); }
  .footer-bottom { gap: 14px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; animation: none !important; }
  .reveal.is-waiting { opacity: 1; transform: none; }
}