:root {
  color-scheme: light;
  --bg: #FBFBFA;
  --bg-panel: #FFFFFF;
  --bg-panel-2: #F4F4F2;
  --border: #E7E6E2;
  --accent: #F25C19;
  --accent-dark: #C2440B;
  --amber: #F5A524;
  --text: #191918;
  --text-muted: #6B6A66;
  --text-faint: #A09E98;
  --success: #1F9D55;
  --warn: #D9930B;
  --error: #D63B3B;
  --c-blue: #2F6BE0;
  --c-red: #D63B3B;
  --c-purple: #8A5CF0;
  --c-green: #1F9D55;
  --accent-rgb: 242 92 25;
  --amber-rgb: 245 165 36;
  --ink-rgb: 25 25 24;
  --white-rgb: 255 255 255;
  --blue-rgb: 47 107 224;
  --green-rgb: 31 157 85;
  --bg-rgb: 251 251 250;
  --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,"SFMono-Regular",Menlo,Consolas,monospace;
  --r-xs: 6px;
  --r-sm: 10px;
  --r-md: 14px;
  --r-lg: 18px;
  --r-xl: 24px;
  --r-pill: 999px;
  --r-circle: 50%;
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-5: 40px;
  --space-6: 48px;
  --space-8: 64px;
  --space-10: 80px;
  --space-12: 96px;
  --gutter: 24px;
  --content-width: 1200px;
  --head-height: 64px;
  --toc-offset: 80px;
  --section-offset: 152px;
  --text-size: 16px;
  --text-small: 14px;
  --display-size: clamp(52px,5vw,68px);
  --heading-size: clamp(28px,3vw,40px);
  --card-heading-size: 28px;
  --weight-body: 400;
  --weight-medium: 600;
  --weight-bold: 700;
  --weight-display: 800;
  --tracking-display: -.03em;
  --tracking-cjk: -.02em;
  --ease: cubic-bezier(.2,.7,.2,1);
  --duration: .2s;
  --shadow-chip: 0 0 0 1px rgb(var(--ink-rgb) / .06),0 8px 18px -10px rgb(var(--ink-rgb) / .28);
  --shadow-disc: 0 0 0 1px rgb(var(--ink-rgb) / .05),0 12px 24px -12px rgb(var(--ink-rgb) / .42);
  --shadow-panel: inset 0 1px 0 rgb(var(--white-rgb) / .9),0 0 0 1px rgb(var(--ink-rgb) / .06),0 24px 64px -24px rgb(var(--accent-rgb) / .12);
  --shadow-button: inset 0 1px 0 rgb(var(--white-rgb) / .35),0 1px 2px rgb(var(--accent-rgb) / .4),0 14px 28px -12px rgb(var(--accent-rgb) / .65);
}
* { box-sizing: border-box; }
html { margin: 0; padding: 0; scroll-padding-top: var(--toc-offset); scroll-behavior: smooth; }
body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: var(--text-size);
  font-weight: var(--weight-body);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}
[hidden] { display: none !important; }
img, video { display: block; max-width: 100%; height: auto; }
svg { flex-shrink: 0; }
button, input, select, textarea { font: inherit; }
button, summary { cursor: pointer; }
button { color: inherit; }
a { color: inherit; text-underline-offset: .2em; }
:where(a,button,input,select,textarea,summary,[tabindex]):focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: var(--r-sm);
}
:where(button,[role="tab"]) { min-height: 24px; min-width: 24px; }
h1,h2,h3,h4,p { margin-top: 0; }
h1,h2,h3 { font-family: var(--font-display); text-wrap: balance; overflow-wrap: break-word; }
h1 { font-size: var(--display-size); font-weight: var(--weight-display); line-height: 1.12; letter-spacing: var(--tracking-display); }
:lang(zh-CN) h1,:lang(zh-TW) h1,:lang(ja) h1,:lang(ko) h1 { letter-spacing: var(--tracking-cjk); }
h2 { font-size: var(--heading-size); line-height: 1.25; font-weight: var(--weight-display); letter-spacing: var(--tracking-cjk); }
h3 { font-size: var(--card-heading-size); line-height: 1.3; font-weight: var(--weight-bold); }
p { margin-bottom: var(--space-3); }
code,kbd,pre { font-family: var(--font-mono); }
code { overflow-wrap: anywhere; border-radius: var(--r-xs); background: var(--bg-panel-2); padding: .12em .3em; }
pre { max-width: 100%; overflow-x: auto; padding: var(--space-3); background: var(--bg-panel-2); border-radius: var(--r-md); }
pre code { padding: 0; overflow-wrap: normal; white-space: pre; }
table { border-collapse: collapse; }
th,td { text-align: left; }
hr { border: 0; border-top: 1px solid var(--border); margin-block: var(--space-5); }
::selection { color: var(--text); background: rgb(var(--accent-rgb) / .18); }
.wrap { width: 100%; max-width: var(--content-width); margin-inline: auto; padding-inline: var(--gutter); min-width: 0; }
.section { padding-top: var(--space-10); padding-bottom: var(--space-10); }
.section-head { max-width: 780px; margin-bottom: var(--space-5); }
.section-head p,.muted { color: var(--text-muted); }
.lead { font-size: 20px; line-height: 1.65; color: var(--text-muted); }
.mono { font-family: var(--font-mono); font-variant-numeric: tabular-nums; }
.no-break { white-space: nowrap; }
.visually-hidden { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; }
.grid { display: grid; gap: var(--space-3); }
.grid > *, .flex-row > *, .head-inner > * { min-width: 0; }
.grid-2 { grid-template-columns: repeat(2,minmax(0,1fr)); }
.grid-3 { grid-template-columns: repeat(3,minmax(0,1fr)); }
.flex-row { display: flex; align-items: center; flex-wrap: wrap; gap: var(--space-2); }
.panel,.card { background: var(--bg-panel); border-radius: var(--r-xl); padding: var(--space-4); box-shadow: var(--shadow-panel); min-width: 0; }
.card-title { font-size: var(--card-heading-size); }
.badge,.chip {
  display: inline-flex; align-items: center; gap: var(--space-1);
  max-width: 100%; min-height: 28px; padding: 4px 10px;
  border-radius: var(--r-pill); background: var(--bg-panel-2);
  font-size: 13px; font-weight: var(--weight-medium); overflow-wrap: anywhere;
}
.badge-accent { background: rgb(var(--accent-rgb) / .14); color: var(--accent-dark); }
.badge-dot::before { content: ""; flex-shrink: 0; width: 6px; height: 6px; border-radius: var(--r-circle); background: var(--accent); }
.data-chip { max-width: 100%; overflow: hidden; white-space: nowrap; text-overflow: ellipsis; }
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 10px;
  min-height: 52px; padding: 12px 26px; border: 0; border-radius: var(--r-md);
  font-size: 17px; font-weight: var(--weight-medium); line-height: 1.5;
  text-decoration: none; white-space: nowrap; flex-shrink: 0; cursor: pointer;
  transition: transform var(--duration) var(--ease),box-shadow var(--duration) var(--ease),background var(--duration) var(--ease);
}
.btn svg { display: block; width: 20px; height: 20px; }
.btn-primary { color: var(--bg-panel); background: linear-gradient(118deg,var(--accent) 0%,var(--accent) 38%,var(--amber) 128%); box-shadow: var(--shadow-button); }
.btn-primary:hover,.btn-primary.is-hover { transform: translateY(-1px); box-shadow: inset 0 1px 0 rgb(var(--white-rgb) / .35),0 1px 2px rgb(var(--accent-rgb) / .4),0 18px 32px -12px rgb(var(--accent-rgb) / .7); }
.btn-soft,.btn-secondary { color: var(--accent-dark); background: rgb(var(--accent-rgb) / .1); }
.btn-soft:hover,.btn-secondary:hover { transform: translateY(-1px); background: rgb(var(--accent-rgb) / .14); }
.btn-ink { color: var(--bg-panel); background: var(--text); }
.btn-outline { background: var(--bg-panel); border: 1px solid var(--border); color: var(--text); }
.btn-small { font-size: var(--text-small); min-height: 40px; padding: 8px 16px; border-radius: var(--r-sm); }
.btn:active,.btn.is-active { transform: translateY(1px); }
.btn:disabled,.btn[aria-disabled="true"] { cursor: not-allowed; background: var(--bg-panel-2); color: var(--text-muted); box-shadow: none; transform: none; }
.btn.is-focus { outline: 2px solid var(--accent); outline-offset: 3px; }
.page-top { position: relative; background: linear-gradient(180deg,rgb(var(--accent-rgb) / .06) 0%,rgb(var(--accent-rgb) / .025) 42%,rgb(var(--accent-rgb) / 0) 74%); }
.site-head { position: relative; z-index: 50; border-bottom: 1px solid rgb(var(--ink-rgb) / .06); }
.head-inner { position: relative; max-width: 1312px; margin: 0 auto; padding: 0 32px; height: var(--head-height); display: flex; align-items: center; flex-wrap: nowrap; gap: 24px; z-index: 53; }
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--text); flex-shrink: 0; }
.brand-logo { display: block; width: 32px; height: 32px; border-radius: var(--r-sm); flex-shrink: 0; }
.brand-word { font-family: var(--font-display); font-weight: var(--weight-display); font-size: 19px; letter-spacing: -.02em; white-space: nowrap; }
.tabs { flex: 1; display: flex; justify-content: center; min-width: 0; }
.tabs ul { list-style: none; margin: 0; padding: 0; display: flex; align-items: center; gap: 2px; }
.tabs a { position: relative; display: flex; align-items: center; height: var(--head-height); padding: 0 6px; font-size: 14px; color: var(--text-muted); text-decoration: none; white-space: nowrap; transition: color var(--duration) var(--ease); }
.tabs a::after { content: ""; position: absolute; left: 11px; right: 11px; bottom: -1px; height: 2px; border-radius: var(--r-xs); background: var(--accent); transform: scaleX(0); transform-origin: center; transition: transform .25s var(--ease); }
.tabs a:hover { color: var(--text); }
.tabs a:hover::after { transform: scaleX(.35); }
.tabs a[aria-current="page"] { color: var(--text); font-weight: var(--weight-medium); }
.tabs a[aria-current="page"]::after { transform: scaleX(1); }
.head-tools { display: flex; align-items: center; gap: 8px; flex-shrink: 0; }
.lang-box { position: relative; }
.lang { display: inline-flex; align-items: center; justify-content: center; gap: 6px; width: auto; min-height: 36px; padding: 0 12px; border: 0; border-radius: var(--r-sm); background: none; color: var(--text-muted); font-size: var(--text-small); white-space: nowrap; cursor: pointer; }
.lang span { white-space: nowrap; }
.lang:hover { background: rgb(var(--ink-rgb) / .04); color: var(--text); }
.lang-panel { position: absolute; right: 0; top: calc(100% + 10px); z-index: 60; width: 180px; padding: var(--space-1); background: var(--bg-panel); border: 1px solid var(--border); border-radius: var(--r-md); box-shadow: var(--shadow-panel); }
.lang-panel a { display: flex; align-items: center; width: 100%; min-height: 44px; padding: 10px 12px; border-radius: var(--r-sm); text-decoration: none; font-size: var(--text-small); }
.lang-panel a:hover,.lang-panel a[aria-current="true"] { background: var(--bg-panel-2); }
.login { display: inline-flex; align-items: center; justify-content: center; height: 36px; padding: 0 18px; border-radius: var(--r-sm); background: var(--text); color: var(--bg-panel); font-size: var(--text-small); font-weight: var(--weight-medium); text-decoration: none; white-space: nowrap; box-shadow: inset 0 1px 0 rgb(var(--white-rgb) / .14),0 6px 14px -8px rgb(var(--ink-rgb) / .6); transition: transform var(--duration) var(--ease); }
.login:hover { transform: translateY(-1px); }
.menu-toggle { display: none; flex-direction: column; align-items: center; justify-content: center; gap: 4px; min-width: 44px; min-height: 44px; padding: 10px; border: 0; border-radius: var(--r-sm); color: var(--text); background: var(--bg-panel-2); }
.menu-line { display: block; width: 20px; height: 2px; background: currentColor; border-radius: var(--r-xs); }
.nav-drawer { position: fixed; top: var(--head-height); left: 0; right: 0; z-index: 52; height: calc(100dvh - var(--head-height)); max-height: calc(100dvh - var(--head-height)); padding: var(--space-2) var(--gutter) var(--space-4); background: var(--bg-panel); overflow-y: auto; overscroll-behavior: contain; }
.nav-drawer a { display: flex; align-items: center; width: 100%; min-height: 44px; padding: 12px 16px; border-radius: var(--r-sm); text-decoration: none; }
.nav-drawer a:hover,.nav-drawer a[aria-current] { background: var(--bg-panel-2); color: var(--accent-dark); }
.drawer-langs { border-top: 1px solid var(--border); margin-top: var(--space-2); padding-top: var(--space-2); }
.nav-veil { position: fixed; inset: var(--head-height) 0 0; z-index: 51; border: 0; background: rgb(var(--ink-rgb) / .2); }
html.nav-open { overflow: hidden; }
.site-footer { border-top: 1px solid var(--border); background: var(--bg-panel-2); padding-top: var(--space-8); padding-bottom: var(--space-4); }
.footer-grid { display: grid; grid-template-columns: 1.2fr 1fr 1fr; gap: var(--space-6); }
.footer-grid > * { min-width: 0; }
.footer-brand p { max-width: 340px; margin-top: var(--space-3); color: var(--text-muted); font-size: var(--text-small); line-height: 1.8; }
.footer-heading { margin: 0 0 var(--space-2); font-size: var(--text-small); font-weight: var(--weight-bold); }
.footer-links { display: grid; grid-template-columns: repeat(2,minmax(0,1fr)); gap: 4px 16px; list-style: none; margin: 0; padding: 0; }
.footer-links a,.footer-languages a,.footer-legal a { display: inline-flex; align-items: center; min-height: 32px; padding-block: 4px; text-decoration: none; font-size: var(--text-small); color: var(--text-muted); }
.footer-links a:hover,.footer-languages a:hover,.footer-legal a:hover { color: var(--accent-dark); text-decoration: underline; }
.footer-languages { display: flex; flex-wrap: wrap; gap: 8px 24px; margin-top: var(--space-5); padding-block: var(--space-2); border-top: 1px solid var(--border); }
.footer-bottom { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: var(--space-2); border-top: 1px solid var(--border); padding-top: var(--space-3); font-size: var(--text-small); color: var(--text-muted); }
.footer-bottom p { margin: 0; }
.footer-legal { display: flex; gap: var(--space-3); flex-wrap: wrap; }
.prose { max-width: 820px; min-width: 0; line-height: 1.9; overflow-wrap: anywhere; }
.prose h2 { margin-top: var(--space-8); margin-bottom: var(--space-3); }
.prose h3 { margin-top: var(--space-5); font-size: 24px; }
.prose li { margin-bottom: var(--space-1); }
.prose a { color: var(--accent-dark); }
.reveal { transition: opacity .35s var(--ease),transform .35s var(--ease); }
.reveal.pending { opacity: 0; transform: translateY(16px); }
.reveal.shown { opacity: 1; transform: none; }
#server-status { position: relative; display: block; min-height: 48px; margin-block: var(--space-3); overflow: hidden; max-width: 100%; }
#server-status + * { margin-top: var(--space-3); }
.decoration-host { position: relative; overflow-x: clip; }
.fl-w,.fill-w { fill: var(--bg-panel); }
.fl-r { fill: var(--c-red); }
.fl-b { fill: var(--c-blue); }
.fill-ink { fill: var(--text); }
.ico-w { fill: none; stroke: var(--bg-panel); stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.ico-w--bold { stroke-width: 2.6; }
.ico-ink { fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.symbol-bank { position: absolute; width: 0; height: 0; overflow: hidden; pointer-events: none; }
@media (max-width:1180px) {
  .tabs { justify-content: flex-start; overflow-x: auto; scrollbar-width: none; }
  .tabs::-webkit-scrollbar { display: none; }
  .head-inner { gap: 16px; }
}
@media (max-width:768px) {
  :root { --gutter: 20px; --display-size: clamp(28px,7vw,40px); --heading-size: 30px; }
  .head-inner { padding-inline: 16px; gap: 12px; }
  .tabs { display: none; }
  .head-tools { margin-left: auto; gap: 4px; }
  .menu-toggle { display: flex; }
  .brand { margin-right: auto; gap: 7px; }
  .lang { padding-inline: 8px; font-size: 12px; }
  .login { padding-inline: 14px; }
  .section { padding-top: var(--space-6); padding-bottom: var(--space-6); }
  .grid-3 { grid-template-columns: repeat(2,minmax(0,1fr)); }
  .footer-grid { grid-template-columns: repeat(2,minmax(0,1fr)); gap: var(--space-4); }
  .footer-brand { grid-column: 1 / -1; }
}
@media (max-width:640px) {
  :root { --gutter: 16px; }
  .no-break { white-space: normal; }
  .tilt,[data-tilt] { transform: none; }
  .decoration-host { max-width: 100%; }
  .grid-2,.grid-3 { grid-template-columns: minmax(0,1fr); }
  .panel,.card { padding: var(--space-3); }
  .btn { padding-inline: 20px; font-size: 16px; }
  .brand-word { font-size: 17px; }
  .brand-logo { width: 28px; height: 28px; }
  .head-inner { gap: 6px; }
  .lang { font-size: 11px; gap: 3px; padding-inline: 5px; }
  .login { padding-inline: 12px; font-size: 13px; }
  .footer-grid { gap: var(--space-4) var(--space-2); }
  .footer-links { grid-template-columns: minmax(0,1fr); }
}
@media (prefers-reduced-motion:reduce) {
  html { scroll-behavior: auto; }
  *,*::before,*::after { animation-duration: .01ms !important; transition-duration: .01ms !important; }
  .reveal,.reveal.pending,.reveal.shown { opacity: 1; transform: none; }
}