:root {
  color-scheme: light;
  --bg: #FCF9F8;
  --bg-panel: #FFFFFF;
  --bg-panel-2: #F4F0EF;
  --border: #E9E2E1;
  --accent: #E63A46;
  --accent-dark: #B4212F;
  --text: #1D1A21;
  --text-muted: #6A6470;
  --success: #1E9E62;
  --warn: #D9940E;
  --error: #C42B23;
  --hero-top: #FFFFFF;
  --hero-bottom: #F7F2F1;
  --violet: #6B5CF5;
  --sky: #3FA9F5;
  --orchid: #D96BE0;
  --grass: #4CC864;
  --amber: #F7A93B;
  --gold: #F7C948;
  --white: #FFFFFF;
  --clear: transparent;
  --sky-soft: color-mix(in srgb, var(--sky) 58%, var(--white));
  --grass-soft: color-mix(in srgb, var(--grass) 68%, var(--gold));
  --white-08: color-mix(in srgb, var(--white) 8%, transparent);
  --white-12: color-mix(in srgb, var(--white) 12%, transparent);
  --white-22: color-mix(in srgb, var(--white) 22%, transparent);
  --white-40: color-mix(in srgb, var(--white) 40%, transparent);
  --white-55: color-mix(in srgb, var(--white) 55%, transparent);
  --white-80: color-mix(in srgb, var(--white) 80%, transparent);
  --ink-veil: color-mix(in srgb, var(--text) 20%, transparent);
  --flag-red: #D7263D;
  --flag-blue: #21468B;
  --flag-navy: #012169;
  --flag-edge: color-mix(in srgb, var(--text) 14%, transparent);
  --shade: color-mix(in srgb, var(--accent-dark) 10%, transparent);
  --shade-strong: color-mix(in srgb, var(--accent-dark) 15%, transparent);
  --focus: color-mix(in srgb, var(--accent) 65%, transparent);
  --shadow-card: 0 30px 60px -28px var(--shade-strong), 0 8px 20px -10px var(--shade);
  --shadow-chip: 0 16px 32px -14px var(--shade-strong), 0 2px 6px var(--shade);
  --shadow-gold: 0 26px 46px -22px color-mix(in srgb, var(--warn) 60%, transparent), 0 4px 12px -4px color-mix(in srgb, var(--warn) 28%, transparent);
  --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-sm: 12px;
  --r-md: 16px;
  --r-menu: 20px;
  --r-icon: 22px;
  --r-card: 26px;
  --r-app: 28px;
  --r-badge: 30px;
  --r-tile: 56px;
  --r-pill: 999px;
  --r-round: 50%;
  --nav-h: 72px;
  --gutter: 24px;
  --wrap: 1200px;
  --reading: 800px;
  --toc-h: 64px;
  --anchor-offset: calc(var(--nav-h) + var(--toc-h) + 24px);
  --time-fast: .2s;
  --time-reveal: .35s;
  --weight-normal: 400;
  --weight-medium: 500;
  --weight-semibold: 600;
  --weight-bold: 700;
  --weight-display: 800;
}
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-padding-top: calc(var(--nav-h) + 16px); scroll-behavior: smooth; }
body { margin: 0; background: var(--bg); color: var(--text); font: var(--weight-normal) 16px/1.6 var(--font-body); -webkit-font-smoothing: antialiased; overflow-x: clip; }
html.nav-open { overflow: hidden; }
[hidden] { display: none !important; }
img { max-width: 100%; height: auto; display: block; }
svg { flex-shrink: 0; }
a { color: inherit; text-decoration: none; }
button, input, select, textarea { font: inherit; color: inherit; }
button { background: none; border: 0; cursor: pointer; }
button, a, summary { -webkit-tap-highlight-color: var(--clear); }
:where(a, button, summary, input, select, textarea, [tabindex]):focus-visible { outline: 3px solid var(--focus); outline-offset: 3px; }
button:disabled, .btn[aria-disabled="true"] { opacity: .5; cursor: not-allowed; }
h1, h2, h3, h4 { font-family: var(--font-display); font-weight: var(--weight-display); line-height: 1.2; margin: 0 0 24px; overflow-wrap: break-word; text-wrap: balance; letter-spacing: -.02em; }
h1 { font-size: clamp(52px, 4.6vw, 66px); line-height: 1.1; }
h2 { font-size: clamp(30px, 3.2vw, 44px); }
h3 { font-size: 24px; }
p { margin: 0 0 20px; }
ul, ol { padding-left: 24px; }
li { margin-bottom: 8px; }
nav ul { list-style: none; margin: 0; padding: 0; }
nav li { margin: 0; }
hr { border: 0; border-top: 1px solid var(--border); margin: 32px 0; }
code, pre, kbd, samp { font-family: var(--font-mono); }
code { overflow-wrap: anywhere; font-size: .9em; background: var(--bg-panel-2); border-radius: var(--r-sm); padding: 2px 5px; }
pre { max-width: 100%; overflow-x: auto; background: var(--bg-panel-2); padding: 24px; border-radius: var(--r-md); }
pre code { padding: 0; overflow-wrap: normal; }
table { border-collapse: collapse; }
th, td { text-align: left; }
.wrap { width: 100%; max-width: var(--wrap); margin-inline: auto; padding-inline: var(--gutter); }
.reading-wrap { width: 100%; max-width: var(--reading); margin-inline: auto; padding-inline: var(--gutter); }
.section { padding-top: 80px; padding-bottom: 80px; }
.section-head { margin-bottom: 40px; max-width: 760px; }
.page-head { padding-top: 64px; padding-bottom: 40px; }
.lead { font-size: 20px; color: var(--text-muted); }
.muted, .h2-sub { color: var(--text-muted); }
.h2-main, .h2-sub { display: block; }
.no-break { white-space: nowrap; }
.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; }
.skip-link { position: fixed; top: 8px; left: 16px; z-index: 100; transform: translateY(-160%); padding: 12px 20px; border-radius: var(--r-pill); background: var(--text); color: var(--white); }
.skip-link:focus { transform: none; }
.grid { display: grid; gap: 24px; }
.grid > *, .wrap > *, .reading-wrap > * { min-width: 0; }
.grid-three { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-two { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.card, .panel { min-width: 0; padding: 32px; border-radius: var(--r-card); background: var(--bg-panel); box-shadow: var(--shadow-card); }
.panel-sunken { padding: 24px; border-radius: var(--r-card); background: var(--bg-panel-2); }
.prose { min-width: 0; overflow-wrap: break-word; }
.prose h2 { margin-top: 56px; }
.prose h3 { margin-top: 32px; }
.prose p, .prose li { line-height: 1.85; }
.prose a:not(.btn) { color: var(--accent-dark); text-decoration: underline; text-underline-offset: 3px; }
.prose section { margin-bottom: 48px; }
.btn { display: inline-flex; align-items: center; justify-content: center; flex-shrink: 0; gap: 8px; min-height: 56px; padding: 12px 32px; border-radius: var(--r-pill); font-size: 17px; font-weight: var(--weight-bold); line-height: 1.4; text-align: center; transition: transform var(--time-fast), background-color var(--time-fast), box-shadow var(--time-fast); }
.btn svg { width: 18px; height: 18px; fill: none; stroke: currentColor; stroke-width: 2.2; stroke-linecap: round; stroke-linejoin: round; }
.btn-main, .btn-primary { background: var(--accent); color: var(--white); box-shadow: inset 1px 1px 0 var(--white-40), 0 16px 30px -14px color-mix(in srgb, var(--accent) 70%, transparent); }
.btn-main:hover, .btn-primary:hover { background: var(--accent-dark); transform: translateY(-2px); }
.btn-soft, .btn-secondary { background: var(--bg-panel-2); color: var(--accent); }
.btn-soft:hover, .btn-secondary:hover { background: var(--border); transform: translateY(-2px); }
.btn-ink { background: var(--text); color: var(--white); }
.btn-small { min-height: 44px; padding: 10px 20px; font-size: 15px; }
.btn:active { transform: translateY(0); }
.cta-pair { margin-top: 32px; display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; }
.topbar, #site-header { position: sticky; top: 0; z-index: 70; height: var(--nav-h); }
.topbar-surface { height: var(--nav-h); background: color-mix(in srgb, var(--bg-panel) 80%, transparent); -webkit-backdrop-filter: saturate(160%) blur(16px); backdrop-filter: saturate(160%) blur(16px); }
.topbar-in { max-width: 1360px; height: 100%; margin: 0 auto; padding: 0 32px; display: flex; flex-wrap: nowrap; align-items: center; gap: 24px; }
.brand { display: inline-flex; align-items: center; gap: 10px; flex-shrink: 0; font-family: var(--font-display); font-weight: var(--weight-display); font-size: 20px; letter-spacing: -.02em; color: var(--text); }
.brand img { width: 36px; height: 36px; flex-shrink: 0; border-radius: var(--r-sm); }
.brand-cn { font-size: 16px; font-weight: var(--weight-medium); color: var(--text-muted); }
.mainnav { flex: 1; min-width: 0; display: flex; justify-content: center; }
.mainnav > ul { display: flex; align-items: center; list-style: none; margin: 0; padding: 0; gap: 4px; }
.mainnav a, .nav-more { display: inline-flex; align-items: center; justify-content: center; gap: 6px; min-height: 40px; padding: 0 16px; border-radius: var(--r-pill); font-size: 15px; font-weight: var(--weight-semibold); white-space: nowrap; transition: background-color var(--time-fast); }
.mainnav a:hover, .nav-more:hover, .mainnav a[aria-current="page"], .nav-more[aria-expanded="true"], .nav-more.is-current { background: var(--bg-panel-2); }
.nav-more svg { width: 12px; height: 12px; fill: none; stroke: currentColor; stroke-width: 2.2; }
.nav-group { position: relative; }
.nav-menu { position: absolute; top: calc(100% + 10px); left: 50%; transform: translateX(-50%); z-index: 82; width: max-content; min-width: 196px; padding: 8px; border-radius: var(--r-menu); background: var(--bg-panel); box-shadow: var(--shadow-card); }
.nav-menu a { display: flex; justify-content: flex-start; width: 100%; border-radius: var(--r-sm); }
.tools { display: flex; align-items: center; flex-shrink: 0; gap: 8px; margin-left: auto; }
.lang-picker { position: relative; }
.lang { display: inline-flex; align-items: center; justify-content: center; gap: 6px; width: auto; min-width: 44px; height: 40px; padding: 0 14px; border-radius: var(--r-pill); font-size: 14px; font-weight: var(--weight-semibold); color: var(--text-muted); white-space: nowrap; }
.lang:hover { background: var(--bg-panel-2); }
.lang span { white-space: nowrap; }
.lang svg { width: 16px; height: 16px; fill: none; stroke: currentColor; stroke-width: 1.8; }
.lang-panel { position: absolute; top: calc(100% + 12px); right: 0; z-index: 84; width: 192px; padding: 8px; background: var(--bg-panel); border-radius: var(--r-menu); box-shadow: var(--shadow-card); }
.lang-panel a { display: flex; align-items: center; width: 100%; min-height: 44px; padding: 10px 14px; border-radius: var(--r-sm); }
.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; gap: 8px; height: 40px; padding: 0 20px; border-radius: var(--r-pill); background: var(--text); color: var(--bg-panel); font-size: 15px; font-weight: var(--weight-bold); white-space: nowrap; transition: transform var(--time-fast); }
.login:hover { transform: translateY(-1px); }
.login svg { width: 16px; height: 16px; fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; }
.nav-toggle { display: none; min-width: 44px; min-height: 44px; align-items: center; justify-content: center; flex-direction: column; gap: 5px; border-radius: var(--r-sm); }
.nav-toggle-line { display: block; width: 20px; height: 2px; background: currentColor; transition: transform var(--time-fast); }
.nav-toggle[aria-expanded="true"] .nav-toggle-line:first-child { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle-line:last-child { transform: translateY(-7px) rotate(-45deg); }
.nav-drawer { position: fixed; top: var(--nav-h); left: 0; right: 0; z-index: 72; height: calc(100dvh - var(--nav-h)); max-height: calc(100dvh - var(--nav-h)); overflow-y: auto; overscroll-behavior: contain; padding: 20px var(--gutter) 40px; background: var(--bg-panel); }
.nav-drawer a { display: flex; align-items: center; width: 100%; min-height: 48px; padding: 12px 16px; border-radius: var(--r-sm); font-weight: var(--weight-semibold); }
.nav-drawer a:hover, .nav-drawer a[aria-current] { background: var(--bg-panel-2); }
.drawer-languages { margin-top: 20px; padding-top: 20px; border-top: 1px solid var(--border); }
.nav-veil { position: fixed; inset: var(--nav-h) 0 0; z-index: 71; background: var(--ink-veil); }
.site-footer { background: var(--bg-panel-2); padding-top: 64px; padding-bottom: 32px; }
.footer-grid { display: grid; grid-template-columns: 1.2fr 1fr 1fr; gap: 48px; }
.footer-grid > * { min-width: 0; }
.footer-intro { margin-top: 20px; max-width: 360px; color: var(--text-muted); }
.footer-title { font-size: 16px; margin-bottom: 16px; }
.footer-links { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 4px 16px; }
.footer-links a, .footer-languages a, .footer-legal a { display: inline-flex; align-items: center; min-height: 32px; font-size: 14px; }
.footer-links a:hover, .footer-languages a:hover, .footer-legal a:hover { text-decoration: underline; text-underline-offset: 4px; }
.footer-languages { margin-top: 32px; display: flex; flex-wrap: wrap; gap: 8px 24px; }
.footer-bottom { border-top: 1px solid var(--border); margin-top: 24px; padding-top: 24px; display: flex; flex-wrap: wrap; justify-content: space-between; gap: 16px; font-size: 13px; color: var(--text-muted); }
.footer-bottom p { margin: 0; }
.footer-legal { display: flex; flex-wrap: wrap; gap: 16px; }
.reveal { transition: opacity var(--time-reveal), transform var(--time-reveal); }
.reveal.pending { opacity: 0; transform: translateY(16px); }
.reveal.shown { opacity: 1; transform: none; }
#server-status { position: relative; display: block; min-height: 100px; overflow: hidden; max-width: 100%; margin-top: 24px; margin-bottom: 24px; }
#server-status + * { margin-top: 24px; }
@media (max-width: 1180px) {
  .mainnav a, .nav-more { padding-inline: 12px; }
  .topbar-in { gap: 16px; }
}
@media (max-width: 960px) {
  .mainnav { display: none; }
  .nav-toggle { display: inline-flex; }
  .topbar-in { justify-content: space-between; padding-inline: 20px; gap: 12px; }
  .tools { margin-left: auto; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
  .footer-brand { grid-column: 1 / -1; }
  .grid-three { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 768px) {
  h1 { font-size: clamp(28px, 8vw, 40px); }
  h2 { font-size: 32px; }
  .section { padding-top: 56px; padding-bottom: 56px; }
  .page-head { padding-top: 40px; padding-bottom: 24px; }
  .btn { min-height: 52px; padding-inline: 26px; }
}
@media (max-width: 640px) {
  :root { --gutter: 20px; }
  .no-break { white-space: normal; }
  .tilt, [data-tilt] { transform: none; }
  .decor, .stripe-halo { max-width: 100%; }
  .grid-three, .grid-two { grid-template-columns: minmax(0, 1fr); }
  .card, .panel { padding: 24px; }
  .topbar-in { padding-inline: 16px; gap: 8px; }
  .brand { font-size: 17px; gap: 7px; }
  .brand img { width: 32px; height: 32px; }
  .tools { gap: 2px; margin-left: auto; }
  .login { padding-inline: 14px; font-size: 14px; }
  .login svg { display: none; }
  .lang { padding-inline: 8px; font-size: 12px; gap: 4px; }
  .lang svg { width: 14px; height: 14px; }
  .footer-grid { grid-template-columns: minmax(0, 1fr); }
  .footer-brand { grid-column: auto; }
  .lead { font-size: 18px; }
}
@media (max-width: 359px) {
  .brand { font-size: 15px; gap: 5px; }
  .brand img { width: 28px; height: 28px; }
  .lang { padding-inline: 5px; }
  .login { padding-inline: 10px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
  .reveal, .reveal.pending { opacity: 1; transform: none; }
}