:root {
  color-scheme: light;
  --bg: #EEF0EF;
  --panel: #FFFFFF;
  --panel-2: #E3E7E5;
  --border: #D6DBD8;
  --accent: #2B50E8;
  --accent-dark: #1B37B5;
  --accent-light: #5B7CF2;
  --accent-soft: #E7ECFD;
  --wine: #6B1B36;
  --text: #15191B;
  --muted: #5A6461;
  --mark: #6F7976;
  --success: #1F9A60;
  --success-soft: #E2F3EA;
  --warn: #C4860F;
  --error: #C5343C;
  --white: #FFFFFF;
  --hero-from: #E9ECEB;
  --hero-to: #D6E1F6;
  --hex-hi: #F4F7FD;
  --hex-mid: #E2E9FA;
  --hex-lo: #C9D6F5;
  --globe-1: #E3EAFB;
  --globe-2: #B8C9F2;
  --globe-3: #8CA3E3;
  --core-1: #B4C6F3;
  --core-2: #DCE4FA;
  --core-3: #F7F9FE;
  --flag-red: #CF2F3E;
  --flag-blue: #26418F;
  --flag-white: #FFFFFF;
  --grid-line: rgba(21,25,27,.04);
  --edge: rgba(196,204,201,.55);
  --ink-a12: rgba(21,25,27,.12);
  --veil: rgba(21,25,27,.28);
  --white-a28: rgba(255,255,255,.28);
  --white-a55: rgba(255,255,255,.55);
  --white-a70: rgba(255,255,255,.7);
  --white-a88: rgba(255,255,255,.88);
  --accent-a10: rgba(43,80,232,.10);
  --accent-a14: rgba(43,80,232,.14);
  --accent-a22: rgba(43,80,232,.22);
  --accent-a32: rgba(43,80,232,.32);
  --success-a18: rgba(31,154,96,.18);
  --clear: transparent;
  --font-display: "Inter", "Noto Sans SC", "PingFang SC", "Hiragino Sans", "Microsoft YaHei", system-ui, sans-serif;
  --font-body: "Inter", "Noto Sans SC", "PingFang SC", "Hiragino Sans", "Microsoft YaHei", system-ui, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
  --weight-regular: 400;
  --weight-heading: 500;
  --weight-strong: 600;
  --text-xs: 12px;
  --text-sm: 14px;
  --text-nav: 15px;
  --text-button: 16px;
  --text-body: 17px;
  --text-subtitle: 20px;
  --text-h3: 24px;
  --text-h2: 34px;
  --text-h1: 64px;
  --leading-body: 1.75;
  --tracking-heading: -.02em;
  --r-panel: 16px;
  --r-card: 10px;
  --r-menu: 12px;
  --r-tile: 8px;
  --r-small: 6px;
  --r-flag: 3px;
  --r-pill: 999px;
  --r-circle: 50%;
  --shadow-float: 0 0 0 1px var(--edge), inset 0 1px 0 var(--white), 0 20px 44px -16px var(--accent-a14), 0 4px 12px -4px var(--accent-a10);
  --shadow-panel: 0 40px 90px -40px var(--accent-a14), inset 0 0 0 1px var(--white-a70);
  --shadow-button: inset 0 1px 0 var(--white-a28), 0 14px 30px -14px var(--accent-a32);
  --gutter: 32px;
  --wrap: 1328px;
  --header-h: 72px;
  --toc-h: 64px;
  --anchor-offset: 152px;
  --ease: .2s ease;
  --reveal-time: .35s;
  --k: 1;
}
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: calc(var(--header-h) + 16px); }
body { margin: 0; background: var(--bg); color: var(--text); font: var(--weight-regular) var(--text-body)/var(--leading-body) var(--font-body); -webkit-font-smoothing: antialiased; }
img, svg { vertical-align: middle; max-width: 100%; }
img { height: auto; }
svg { flex-shrink: 0; }
button, input, select, textarea { font: inherit; color: inherit; }
button, summary { cursor: pointer; }
button { background: var(--clear); }
a { color: var(--accent-dark); text-underline-offset: .2em; }
a, button, summary { -webkit-tap-highlight-color: var(--accent-a14); }
:where(a, button, summary, input, select, textarea, [tabindex]):focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; }
[hidden] { display: none !important; }
h1, h2, h3 { font-family: var(--font-display); font-weight: var(--weight-heading); letter-spacing: var(--tracking-heading); overflow-wrap: break-word; text-wrap: balance; }
h1 { font-size: var(--text-h1); line-height: 1.1; }
h2 { font-size: var(--text-h2); line-height: 1.25; }
h3 { font-size: var(--text-h3); line-height: 1.35; }
p { margin: 0 0 1.25em; }
strong { font-weight: var(--weight-strong); }
code { font-family: var(--font-mono); overflow-wrap: anywhere; }
pre { max-width: 100%; overflow-x: auto; padding: 24px; border-radius: var(--r-card); background: var(--panel-2); font-family: var(--font-mono); }
pre code { overflow-wrap: normal; white-space: pre; }
hr { border: 0; border-top: 1px solid var(--border); margin-block: 32px; }
.wrap { width: 100%; max-width: var(--wrap); margin-inline: auto; padding-inline: var(--gutter); min-width: 0; }
.section { padding-top: 80px; padding-bottom: 80px; }
.reading-wrap, .prose { max-width: 880px; min-width: 0; }
.prose { overflow-wrap: anywhere; }
.prose h2 { margin-top: 2em; }
.prose li { margin-block: .5em; }
.prose img { border-radius: var(--r-card); }
.no-break { white-space: nowrap; }
.muted { color: var(--muted); }
.mono { font-family: var(--font-mono); font-variant-numeric: tabular-nums; }
.eyebrow { margin: 0; color: var(--accent); font: var(--weight-heading) var(--text-xs)/1.2 var(--font-mono); letter-spacing: .12em; }
.grid { display: grid; gap: 24px; }
.grid > *, .hero-inner > *, .footer-grid > * { min-width: 0; }
.grid-2 { grid-template-columns: repeat(2,minmax(0,1fr)); }
.grid-3 { grid-template-columns: repeat(3,minmax(0,1fr)); }
.card, .panel { padding: 28px; background: var(--panel); border-radius: var(--r-card); box-shadow: var(--shadow-float); min-width: 0; }
.panel { border-radius: var(--r-panel); }
.decorated, .grid-board { position: relative; overflow-x: clip; }
.grid-board { background-image: linear-gradient(var(--grid-line) 1px,var(--clear) 1px),linear-gradient(90deg,var(--grid-line) 1px,var(--clear) 1px); background-size: 56px 56px; }
#server-status { display: block; position: static; min-height: 160px; max-width: 100%; overflow: hidden; margin-block: 24px; }
#server-status + * { margin-top: 32px; }
.reveal { transition: opacity var(--reveal-time) ease, transform var(--reveal-time) ease; }
.reveal.pending { opacity: 0; transform: translateY(16px); }
.reveal.shown { opacity: 1; transform: none; }
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 10px; min-height: 52px; padding: 0 28px; border: 0; border-radius: var(--r-pill); font: var(--weight-heading) var(--text-button)/1.2 var(--font-body); text-decoration: none; text-align: center; transition: transform var(--ease), box-shadow var(--ease), background-color var(--ease); }
.btn svg { width: 16px; height: 16px; }
.btn-solid, .btn-primary { color: var(--white); background: linear-gradient(180deg,var(--accent-light) -40%,var(--accent) 62%); box-shadow: var(--shadow-button); }
.btn-solid:hover, .btn-primary:hover { transform: translateY(-1px); box-shadow: inset 0 1px 0 var(--white-a28),0 18px 34px -14px var(--accent-a32); }
.btn-line, .btn-secondary { color: var(--accent-dark); background: var(--white-a55); box-shadow: inset 0 0 0 1.5px var(--accent); }
.btn-line:hover, .btn-secondary:hover { background: var(--white); }
.btn:active { transform: translateY(1px); }
.btn:disabled, .btn[aria-disabled="true"] { opacity: .5; cursor: not-allowed; transform: none; }
.btn-small { min-height: 40px; padding-inline: 20px; font-size: var(--text-sm); }
.cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 32px; }
#site-header { position: relative; z-index: 100; min-height: var(--header-h); }
.top { position: relative; z-index: 103; display: flex; align-items: center; flex-wrap: nowrap; gap: 32px; height: var(--header-h); padding: 0 88px; background: var(--bg); }
.brand { display: inline-flex; align-items: center; gap: 10px; flex-shrink: 0; color: var(--text); font: var(--weight-strong) 19px/1 var(--font-display); letter-spacing: -.01em; text-decoration: none; }
.brand img { width: 34px; height: 34px; flex-shrink: 0; }
.brand-zh { color: var(--muted); font-weight: var(--weight-regular); }
.nav { display: flex; flex: 1; min-width: 0; justify-content: center; align-items: center; }
.nav-list { display: flex; align-items: center; list-style: none; margin: 0; padding: 0; gap: 4px; }
.nav a, .more-btn { display: inline-flex; align-items: center; gap: 6px; min-height: 38px; padding: 0 15px; border: 0; border-radius: var(--r-pill); background: var(--clear); color: var(--muted); font: var(--weight-regular) var(--text-nav)/1.2 var(--font-body); text-decoration: none; white-space: nowrap; }
.nav a:hover, .more-btn:hover { color: var(--text); background: var(--white-a55); }
.nav a[aria-current="page"], .more-btn.is-current { color: var(--text); background: var(--white-a70); box-shadow: 0 0 0 1px var(--edge); font-weight: var(--weight-heading); }
.chev { width: 12px; height: 12px; }
.more { position: relative; }
.more-menu { position: absolute; top: calc(100% + 10px); left: 50%; z-index: 110; min-width: 220px; padding: 8px; transform: translateX(-50%); border-radius: var(--r-menu); background: var(--panel); box-shadow: var(--shadow-float); display: none; }
.more.is-open .more-menu { display: block; }
.more-group { display: block; padding: 8px 10px 4px; color: var(--mark); font: var(--weight-heading) 11px/1.4 var(--font-mono); letter-spacing: .06em; }
.more-menu a { display: flex; width: 100%; min-height: 40px; padding-inline: 10px; border-radius: var(--r-tile); color: var(--text); font-size: var(--text-sm); }
.more-menu a:hover { background: var(--accent-soft); color: var(--accent-dark); }
.tools { display: flex; align-items: center; gap: 6px; flex-shrink: 0; }
.language { position: relative; }
.lang { display: inline-flex; align-items: center; justify-content: center; gap: 7px; width: auto; min-width: 44px; min-height: 38px; padding: 0 12px; border: 0; border-radius: var(--r-pill); color: var(--text); background: var(--clear); font: var(--weight-regular) var(--text-sm)/1 var(--font-body); white-space: nowrap; }
.lang span { white-space: nowrap; }
.lang:hover { background: var(--white-a55); }
.lang svg { width: 16px; height: 16px; }
.lang-panel { display: none; position: absolute; z-index: 112; right: 0; top: calc(100% + 12px); min-width: 180px; padding: 8px; border-radius: var(--r-menu); background: var(--panel); box-shadow: var(--shadow-float); }
.language.is-open .lang-panel { display: block; }
.lang-panel a { display: flex; align-items: center; min-height: 44px; padding: 8px 12px; color: var(--text); text-decoration: none; border-radius: var(--r-tile); font-size: var(--text-sm); }
.lang-panel a:hover, .lang-panel a[aria-current="true"] { background: var(--accent-soft); color: var(--accent-dark); }
.login { display: inline-flex; align-items: center; justify-content: center; gap: 8px; min-height: 40px; padding: 0 20px 0 16px; border-radius: var(--r-pill); background: var(--text); color: var(--white); font: var(--weight-heading) 14.5px/1 var(--font-body); text-decoration: none; white-space: nowrap; box-shadow: inset 0 1px 0 var(--white-a28),0 10px 22px -12px var(--accent-a32); }
.login svg { width: 16px; height: 16px; }
.menu-toggle { display: none; align-items: center; justify-content: center; flex-direction: column; gap: 5px; min-width: 44px; min-height: 44px; padding: 10px; border: 1px solid var(--border); border-radius: var(--r-tile); color: var(--text); background: var(--panel); }
.menu-line { display: block; width: 20px; height: 2px; background: currentColor; transition: transform var(--ease),opacity var(--ease); }
.menu-toggle[aria-expanded="true"] .menu-line:first-child { transform: translateY(7px) rotate(45deg); }
.menu-toggle[aria-expanded="true"] .menu-line:nth-child(2) { opacity: 0; }
.menu-toggle[aria-expanded="true"] .menu-line:last-child { transform: translateY(-7px) rotate(-45deg); }
.mobile-drawer { display: none; position: fixed; z-index: 102; top: var(--header-h); inset-inline: 0; height: calc(100dvh - var(--header-h)); max-height: calc(100dvh - var(--header-h)); overflow-y: auto; overscroll-behavior: contain; padding: 20px var(--gutter) 40px; background: var(--panel); }
.mobile-drawer.is-open { display: block; }
.mobile-drawer a { display: flex; width: 100%; align-items: center; min-height: 48px; padding: 12px 16px; border-bottom: 1px solid var(--border); color: var(--text); text-decoration: none; }
.mobile-drawer a[aria-current] { color: var(--accent-dark); background: var(--accent-soft); }
.drawer-label { display: block; margin-top: 24px; padding: 12px 16px; color: var(--muted); font-size: var(--text-sm); }
.menu-veil { display: none; position: fixed; z-index: 101; top: var(--header-h); bottom: 0; inset-inline: 0; border: 0; background: var(--veil); }
.menu-veil.is-open { display: block; }
html.nav-open { overflow: hidden; }
.site-footer { margin-top: 48px; padding-top: 64px; padding-bottom: 32px; border-top: 1px solid var(--border); background: linear-gradient(180deg,var(--bg),var(--panel-2)); }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 40px; }
.footer-about p { margin-top: 20px; max-width: 360px; color: var(--muted); font-size: var(--text-sm); }
.footer-title { margin: 0 0 16px; font-size: var(--text-sm); font-weight: var(--weight-heading); }
.footer-links { display: grid; gap: 4px; }
.footer-links a { display: flex; align-items: center; min-height: 32px; color: var(--muted); font-size: var(--text-sm); text-decoration: none; }
.footer-links a:hover { color: var(--accent-dark); }
.footer-bottom { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: center; gap: 16px; margin-top: 40px; padding-top: 24px; border-top: 1px solid var(--border); color: var(--muted); font-size: var(--text-xs); }
.footer-legal { display: flex; flex-wrap: wrap; gap: 20px; }
.footer-legal a { display: inline-flex; align-items: center; min-height: 28px; color: var(--muted); }
@media (max-width:1320px) {
  :root { --k: .86; }
  .top { padding-inline: 64px; gap: 20px; }
  .nav a, .more-btn { padding-inline: 12px; }
}
@media (max-width:1100px) {
  .top { padding-inline: 32px; gap: 16px; }
  .nav a, .more-btn { padding-inline: 9px; }
}
@media (max-width:980px) {
  .nav { display: none; }
  .tools { margin-left: auto; }
  .menu-toggle { display: inline-flex; }
  .footer-grid { grid-template-columns: repeat(2,minmax(0,1fr)); }
}
@media (min-width:981px) {
  .mobile-drawer.is-open, .menu-veil.is-open { display: none; }
  html.nav-open { overflow: auto; }
}
@media (max-width:768px) {
  :root { --text-h1: 40px; --text-h2: 28px; --gutter: 24px; }
  .grid-3 { grid-template-columns: 1fr; }
  .section { padding-top: 48px; padding-bottom: 48px; }
}
@media (max-width:640px) {
  :root { --gutter: 20px; --text-body: 16px; --text-h2: 26px; }
  .no-break { white-space: normal; }
  .top { padding-inline: 16px; gap: 10px; }
  .brand { gap: 7px; font-size: var(--text-body); }
  .brand img { width: 30px; height: 30px; }
  .tools { margin-left: auto; gap: 4px; }
  .lang { padding-inline: 8px; }
  .lang .chev { display: none; }
  .lang span { display: none; }
  .login { min-height: 38px; padding-inline: 14px; font-size: var(--text-sm); }
  .grid-2, .footer-grid { grid-template-columns: 1fr; }
  .card, .panel { padding: 22px; }
  .tilt, [data-tilt] { transform: none; }
  .decorated, .grid-board { max-width: 100%; overflow-x: clip; }
  .footer-grid { gap: 28px; }
}
@media (max-width:360px) {
  :root { --gutter: 16px; }
  .top { padding-inline: 12px; gap: 6px; }
  .brand { font-size: var(--text-nav); }
  .login svg { display: none; }
  .login { padding-inline: 12px; }
}
@media (prefers-reduced-motion:reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition-duration: 0s !important; }
  .reveal, .reveal.pending { opacity: 1; transform: none; }
}