:root {
  --bg: #000000;
  --bg-panel: #0B0B0C;
  --bg-panel-2: #151517;
  --bg-panel-3: #1C1C1F;
  --border: #232326;
  --border-strong: #2E2E33;
  --accent: #1A8CFF;
  --accent-dark: #0B5FD1;
  --text: #F2F2F3;
  --text-muted: #8D8D93;
  --text-dim: #55555B;
  --success: #4CC38A;
  --warn: #E2B04F;
  --error: #EF5A5F;
  --btn-light-hover: #DADADD;
  --code-key: #B8B8BE;
  --code-punc: #98989F;
  --code-gutter: #34343A;
  --canvas-ink: #01040A;
  --canvas-ink-top: #000206;
  --clear: transparent;
  --accent-a04: rgba(26,140,255,.04);
  --accent-a08: rgba(26,140,255,.08);
  --accent-a12: rgba(26,140,255,.12);
  --accent-a22: rgba(26,140,255,.22);
  --accent-a30: rgba(26,140,255,.30);
  --accent-a45: rgba(26,140,255,.45);
  --accent-dark-a50: rgba(11,95,209,.50);
  --hair-light: rgba(255,255,255,.045);
  --hair-light-strong: rgba(255,255,255,.22);
  --shadow-ink: rgba(0,0,0,.9);
  --veil: rgba(0,0,0,.72);
  --font-display: "Inter","Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  --font-body: "Inter","Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  --font-mono: "JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;
  --weight-normal: 400;
  --weight-medium: 500;
  --r-xl: 28px;
  --r-lg: 14px;
  --r-md: 10px;
  --r-sm: 7px;
  --r-xs: 4px;
  --r-chrome: 8px;
  --r-add: 5px;
  --r-tool: 12px;
  --r-mobile: 22px;
  --r-pill: 999px;
  --r-circle: 50%;
  --gutter: 32px;
  --wrap: 1200px;
  --read: 800px;
  --head-width: 1280px;
  --head-height: 60px;
  --space-section: 88px;
  --size-h1: clamp(34px,2.2vw + 16px,48px);
  --size-h2: 32px;
  --size-h3: 22px;
  --size-body: 15px;
  --ease: cubic-bezier(.2,.7,.2,1);
  --duration-fast: .15s;
  --duration-reveal: .5s;
  color-scheme: dark;
}
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 88px; }
html, body { margin: 0; background: var(--bg); color: var(--text); }
body {
  font-family: var(--font-body);
  font-size: var(--size-body);
  font-weight: var(--weight-normal);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}
html.nav-open { overflow: hidden; }
[hidden] { display: none !important; }
a { color: var(--accent); text-decoration: none; text-underline-offset: 4px; }
a:hover { text-decoration: underline; }
img, svg { display: block; max-width: 100%; }
img { height: auto; }
svg, .badge-dot, .icon { flex-shrink: 0; }
button, input, select, textarea { font: inherit; }
button { cursor: pointer; }
button, input, select, textarea { max-width: 100%; }
button { color: var(--text); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: var(--r-sm); }
::selection { background: var(--accent); color: var(--bg); }
h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: var(--weight-normal);
  line-height: 1.2;
  letter-spacing: -.02em;
  text-wrap: balance;
  overflow-wrap: break-word;
}
h1 { font-size: var(--size-h1); line-height: 1.1; }
h2 { font-size: var(--size-h2); }
h3 { font-size: var(--size-h3); }
p { margin-top: 0; }
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; border: 1px solid var(--border); border-radius: var(--r-lg); background: var(--bg-panel); color: var(--text); }
pre code { overflow-wrap: normal; word-break: normal; white-space: pre; }
hr { border: 0; border-top: 1px solid var(--border); margin-block: 32px; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; }
.nowrap { white-space: nowrap; }
.muted { color: var(--text-muted); }
.mono { font-family: var(--font-mono); }
.wrap { width: 100%; max-width: calc(var(--wrap) + var(--gutter) * 2); margin-inline: auto; padding-inline: var(--gutter); }
.read-wrap { width: 100%; max-width: calc(var(--read) + var(--gutter) * 2); margin-inline: auto; padding-inline: var(--gutter); }
.section { padding-top: var(--space-section); padding-bottom: var(--space-section); }
.section-head { margin-bottom: 32px; }
.section-head h2 { margin: 12px 0; }
.section-head p { max-width: 640px; color: var(--text-muted); }
.decorated, .hero { overflow-x: clip; }
.grid { display: grid; gap: 24px; }
.grid-2 { grid-template-columns: repeat(2,minmax(0,1fr)); }
.grid-3 { grid-template-columns: repeat(3,minmax(0,1fr)); }
.grid > *, .head-row > *, .footer-grid > *, .bench > *, .feature-layout > * { min-width: 0; }
.stack > * + * { margin-top: 20px; }
.card, .panel { min-width: 0; padding: 28px; border: 1px solid var(--border); border-radius: var(--r-xl); background: var(--bg-panel); color: var(--text); }
.card h3 { margin-top: 0; }
.card p, .panel p { color: var(--text-muted); }
.card > :last-child, .panel > :last-child { margin-bottom: 0; }
.eyebrow { margin: 0; font: 12px/1.6 var(--font-mono); color: var(--text-muted); letter-spacing: .01em; }
.btns { display: flex; flex-wrap: wrap; gap: 10px; }
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 9px;
  min-height: 44px; padding: 10px 20px; border: 1px solid var(--clear);
  border-radius: var(--r-md); font-size: 15px; font-weight: var(--weight-medium);
  line-height: 22px; letter-spacing: -.005em;
  background: var(--bg-panel-2); color: var(--text);
  text-align: center; transition: background-color var(--duration-fast) var(--ease);
}
.btn:hover { text-decoration: none; background: var(--bg-panel-3); color: var(--text); }
.btn svg { width: 16px; height: 16px; fill: none; stroke: currentColor; stroke-width: 1.6; stroke-linecap: round; stroke-linejoin: round; }
.btn-primary { background: var(--text); color: var(--bg); }
.btn-primary:hover, .btn-primary.is-hover { background: var(--btn-light-hover); color: var(--bg); }
.btn-ghost { background: var(--bg-panel-2); color: var(--text); }
.btn-ghost.is-hover { background: var(--bg-panel-3); color: var(--text); }
.btn-outline { border-color: var(--border-strong); background: var(--bg); color: var(--text); }
.btn:active, .btn.is-active { border-color: var(--accent); }
.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: 2px solid var(--accent); outline-offset: 3px; }
.site-head, #site-header { position: sticky; top: 0; z-index: 50; background: var(--bg); color: var(--text); }
.head-row {
  position: relative; width: 100%; max-width: min(100%,calc(var(--head-width) + var(--gutter) * 2));
  margin-inline: auto; padding-inline: var(--gutter);
  min-height: var(--head-height); display: flex; align-items: center; gap: 24px;
}
.brand { display: inline-flex; align-items: center; gap: 10px; flex-shrink: 0; color: var(--text); font-size: 15px; letter-spacing: -.01em; }
.brand:hover { text-decoration: none; }
.brand img { width: 26px; height: 26px; flex-shrink: 0; }
.nav { margin-left: auto; min-width: 0; }
.nav ul { display: flex; align-items: center; list-style: none; margin: 0; padding: 0; gap: 0; }
.nav li { display: flex; align-items: center; white-space: nowrap; font-size: 14px; color: var(--text-muted); }
.nav li + li::before { content: "·"; padding-inline: 11px; color: var(--text-dim); }
.nav a { padding-block: 6px; color: var(--text-muted); }
.nav a:hover, .nav a[aria-current="page"] { color: var(--text); text-decoration: none; }
.head-tools { display: flex; align-items: center; gap: 8px; flex-shrink: 0; }
.lang-wrap { position: relative; }
.lang {
  display: inline-flex; align-items: center; gap: 6px; min-height: 34px; padding: 6px 12px;
  border: 0; border-radius: var(--r-md); background: var(--bg-panel-2); color: var(--text);
  font-size: 13.5px; white-space: nowrap; list-style: none;
}
.lang:hover { background: var(--bg-panel-3); color: var(--text); }
.lang::-webkit-details-marker { display: none; }
.lang-caret { color: var(--text-muted); font-size: 11px; }
.lang-menu { position: absolute; top: calc(100% + 8px); right: 0; z-index: 55; min-width: 172px; padding: 6px; border: 1px solid var(--border); border-radius: var(--r-lg); background: var(--bg-panel); color: var(--text); box-shadow: 0 20px 40px var(--shadow-ink); }
.lang-menu a { display: flex; align-items: center; min-height: 44px; padding: 10px 12px; border-radius: var(--r-sm); color: var(--text-muted); }
.lang-menu a:hover, .lang-menu a[aria-current="true"] { background: var(--bg-panel-2); color: var(--text); text-decoration: none; }
.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-md); background: var(--bg-panel); color: var(--text); }
.menu-toggle svg { width: 20px; height: 20px; fill: none; stroke: currentColor; stroke-width: 1.6; }
.mobile-drawer { position: absolute; top: 100%; left: 0; right: 0; z-index: 54; max-height: calc(100dvh - var(--head-height)); overflow-y: auto; overscroll-behavior: contain; padding: 16px var(--gutter) 24px; border-bottom: 1px solid var(--border); background: var(--bg); color: var(--text); }
.mobile-drawer ul { list-style: none; margin: 0; padding: 0; }
.mobile-drawer a { display: flex; align-items: center; width: 100%; min-height: 46px; padding: 10px 12px; color: var(--text-muted); border-radius: var(--r-sm); }
.mobile-drawer a:hover, .mobile-drawer a[aria-current] { background: var(--bg-panel-2); color: var(--text); text-decoration: none; }
.drawer-languages { margin-top: 16px !important; border-top: 1px solid var(--border); padding-top: 12px !important; }
.nav-veil { position: fixed; inset: var(--head-height) 0 0; z-index: 40; border: 0; background: var(--veil); color: var(--text); }
.site-footer { margin-top: 48px; padding-top: 48px; padding-bottom: 112px; border-top: 1px solid var(--border); background: var(--bg); color: var(--text); }
.footer-grid { display: grid; grid-template-columns: 1.4fr .8fr 1.2fr; gap: 48px; }
.footer-brand p { margin-top: 18px; max-width: 360px; color: var(--text-muted); font-size: 14px; }
.footer-title { margin: 0 0 14px; font-size: 14px; font-weight: var(--weight-medium); }
.footer-links { list-style: none; margin: 0; padding: 0; }
.footer-links li { margin-block: 8px; }
.footer-links a, .footer-languages a, .footer-bottom a { color: var(--text-muted); font-size: 13px; }
.footer-links a:hover, .footer-languages a:hover, .footer-bottom a:hover { color: var(--text); }
.footer-languages { display: flex; flex-wrap: wrap; gap: 12px 20px; margin-top: 32px; }
.footer-languages a[aria-current="true"] { color: var(--text); }
.footer-bottom { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px 24px; margin-top: 24px; padding-top: 20px; border-top: 1px solid var(--border); color: var(--text-muted); font-size: 12px; }
.footer-legal { display: flex; flex-wrap: wrap; gap: 20px; }
.prose { min-width: 0; line-height: 1.9; }
.prose h2 { margin-top: 56px; }
.prose h3 { margin-top: 32px; }
.prose p, .prose li { color: var(--text-muted); }
.prose strong { color: var(--text); }
.prose :is(ul,ol) { padding-left: 1.5em; }
.prose :is(section,div) { min-width: 0; max-width: 100%; }
.reveal { opacity: 1; transform: none; }
.reveal.is-waiting { opacity: 0; transform: translateY(16px); transition: opacity var(--duration-reveal) var(--ease),transform var(--duration-reveal) var(--ease); }
.reveal.shown { opacity: 1; transform: none; }
@media (max-width: 1280px) {
  .nav li + li::before { padding-inline: 8px; }
  html:not([lang="zh-CN"]):not([lang="zh-TW"]) .head-row > .nav { display: none; }
  html:not([lang="zh-CN"]):not([lang="zh-TW"]) .menu-toggle { display: inline-flex; }
  html:not([lang="zh-CN"]):not([lang="zh-TW"]) .head-tools { margin-left: auto; }
}
@media (min-width: 981px) {
  html[lang="zh-CN"] .mobile-drawer, html[lang="zh-TW"] .mobile-drawer { display: none; }
}
@media (max-width: 980px) {
  .head-row > .nav { display: none; }
  .head-tools { margin-left: auto; }
  .menu-toggle { display: inline-flex; }
  .grid-3 { grid-template-columns: repeat(2,minmax(0,1fr)); }
  .footer-grid { gap: 28px; grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
}
@media (max-width: 768px) {
  :root { --gutter: 16px; --space-section: 56px; --size-h1: clamp(24px,6.6vw,30px); --size-h2: 26px; --size-h3: 20px; }
  h1 { line-height: 1.15; }
  .head-row { gap: 12px; }
  .lang { font-size: 12.5px; min-height: 34px; padding-inline: 10px; }
  .grid-2, .grid-3 { grid-template-columns: minmax(0,1fr); }
  .card, .panel { padding: 20px; }
  .footer-grid { grid-template-columns: minmax(0,1fr); }
  .footer-brand { grid-column: auto; }
  .btn { padding-inline: 16px; font-size: 14.5px; }
}
@media (max-width: 640px) {
  .tilt, [data-tilt] { transform: none !important; }
  .brand { font-size: 14px; gap: 8px; }
  .head-tools { gap: 6px; margin-left: auto; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
  .reveal.is-waiting { opacity: 1; transform: none; }
}