:root {
  color-scheme: dark;
  --bg: #0b2a2a;
  --bg-panel: #103837;
  --bg-panel-2: #164a47;
  --border: #2b5f5a;
  --accent: #ff5f97;
  --accent-dark: #d93d78;
  --text: #eef7f5;
  --text-muted: #9fc2bc;
  --success: #19d3a2;
  --warn: #f5b942;
  --error: #ff6a4d;
  --violet: #a95cf5;
  --block-from: #6a2a9a;
  --block-to: #a8285a;
  --nav-bg: #ffffff;
  --nav-ink: #0b2a2a;
  --nav-sep: #9fc2bc;
  --nav-mark-bg: #e7f1ef;
  --nav-mark-line: #c9dcd8;
  --phone-body: #082222;
  --island: #031212;
  --mask-on: #ffffff;
  --mask-off: #000000;
  --clear: transparent;
  --screen-a: rgba(25, 211, 162, .30);
  --screen-b: rgba(169, 92, 245, .34);
  --screen-bar: rgba(238, 247, 245, .10);
  --screen-bar-2: rgba(238, 247, 245, .05);
  --grid-dot: rgba(159, 194, 188, .22);
  --glow-teal: rgba(25, 211, 162, .30);
  --glow-pink: rgba(255, 95, 151, .28);
  --glow-teal-hot: rgba(25, 211, 162, .55);
  --glow-pink-hot: rgba(255, 95, 151, .55);
  --ring-success: rgba(25, 211, 162, .22);
  --hairline: rgba(238, 247, 245, .08);
  --veil: rgba(2, 14, 14, .72);
  --shadow-float: 0 1px 0 rgba(238, 247, 245, .05) inset, 0 26px 48px -18px rgba(2, 14, 14, .85), 0 6px 16px -4px rgba(2, 14, 14, .45);
  --shadow-phone: 0 40px 80px -30px rgba(2, 14, 14, .9), 0 0 0 6px rgba(25, 211, 162, .04);
  --shadow-btn: 0 10px 26px -10px rgba(255, 95, 151, .65);
  --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', 'SF Mono', ui-monospace, Menlo, Consolas, monospace;
  --r-card: 10px;
  --r-btn: 6px;
  --r-pill: 999px;
  --r-block: 16px;
  --r-group: 8px;
  --r-mark: 9px;
  --r-shot: 10px;
  --r-phone: 50px;
  --r-screen: 41px;
  --r-round: 50%;
  --nav-h: 64px;
  --wrap: 1280px;
  --reading: 820px;
  --gutter: 40px;
  --section-space: 144px;
  --title-size: clamp(34px, calc(2.2vw + 16px), 48px);
  --h2-size: clamp(26px, 3vw, 40px);
  --h3-size: clamp(20px, 2vw, 26px);
  --body-size: 16px;
  --small-size: 13px;
  --tracking-title: -.02em;
  --tracking-label: .12em;
  --weight-regular: 400;
  --weight-medium: 500;
  --weight-bold: 700;
  --ease: cubic-bezier(.2, .65, .3, 1);
  --fast: .2s;
  --reveal-time: .65s;
}

*, *::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(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: var(--body-size);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
[hidden] { display: none !important; }
img, svg { display: block; max-width: 100%; }
svg { flex-shrink: 0; }
button, input, select, textarea { font: inherit; }
button, a { -webkit-tap-highlight-color: var(--clear); }
button { cursor: pointer; }
a { color: var(--accent); text-decoration-thickness: 1px; text-underline-offset: .22em; }
a:hover { text-decoration: underline; }
button:focus-visible, a:focus-visible, summary:focus-visible, [tabindex]:focus-visible {
  outline: 2px solid var(--success);
  outline-offset: 4px;
}
button:disabled, .btn[aria-disabled="true"] { opacity: .5; cursor: not-allowed; box-shadow: none; }
h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: var(--weight-regular);
  letter-spacing: var(--tracking-title);
  line-height: 1.2;
  text-wrap: balance;
  overflow-wrap: break-word;
}
h1 { font-size: var(--title-size); line-height: 1.14; }
h2 { font-size: var(--h2-size); }
h3 { font-size: var(--h3-size); }
p, ul, ol, dl, figure, pre { margin-top: 0; }
p { margin-bottom: 1.25em; }
strong, b { font-weight: var(--weight-medium); }
small { font-size: var(--small-size); }
code, pre, kbd { font-family: var(--font-mono); }
code { overflow-wrap: anywhere; }
pre {
  max-width: 100%;
  min-width: 0;
  overflow-x: auto;
  overscroll-behavior-inline: contain;
  padding: 24px;
  border: 1px solid var(--border);
  border-radius: var(--r-card);
  background: var(--bg);
  color: var(--text);
  font-size: 13px;
  line-height: 1.9;
  tab-size: 2;
}
pre code { white-space: pre; overflow-wrap: normal; word-break: normal; }
hr { border: 0; border-top: 1px solid var(--border); margin-block: 40px; }
.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.reading { max-width: calc(var(--reading) + var(--gutter) * 2); }
.section { padding-top: var(--section-space); padding-bottom: 0; }
.section:last-child { padding-bottom: var(--section-space); }
.section-head { max-width: 760px; margin-bottom: 36px; }
.section-head h2 { margin: 12px 0 20px; }
.eyebrow {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: var(--tracking-label);
  text-transform: uppercase;
}
.muted { color: var(--text-muted); }
.nowrap { white-space: nowrap; }
.grid-two, .grid-three { display: grid; gap: 24px; }
.grid-two { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-three { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-two > *, .grid-three > *, .hero-in > *, .footer-grid > * { min-width: 0; }
.stack > * + * { margin-top: 24px; }
.flow-row { display: flex; flex-wrap: wrap; align-items: center; gap: 14px; }
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}
.skip-link {
  position: fixed;
  top: 8px;
  left: var(--gutter);
  z-index: 100;
  transform: translateY(-160%);
  padding: 10px 16px;
  border-radius: var(--r-btn);
  background: var(--text);
  color: var(--bg);
}
.skip-link:focus { transform: none; }
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 48px;
  padding: 11px 22px;
  border: 1px solid var(--clear);
  border-radius: var(--r-btn);
  font-size: 15px;
  font-weight: var(--weight-medium);
  letter-spacing: .005em;
  line-height: 1.5;
  text-decoration: none;
  text-align: center;
  transition: background-color var(--fast) var(--ease), border-color var(--fast) var(--ease);
}
.btn svg { width: 18px; height: 18px; }
.btn:hover { text-decoration: none; }
.btn-primary { background: var(--accent); color: var(--bg); box-shadow: var(--shadow-btn); }
.btn-primary:hover, .btn-primary.is-hover { background: var(--accent-dark); color: var(--bg); }
.btn-ghost { border-color: var(--success); background: var(--clear); color: var(--text); }
.btn-ghost:hover, .btn-ghost.is-hover { background: var(--bg-panel); color: var(--text); }
.btn-ghost .arrow { color: var(--success); }
.btn.is-focus { outline: 2px solid var(--success); outline-offset: 4px; }
.card, .panel {
  padding: 28px;
  border: 1px solid var(--border);
  border-radius: var(--r-card);
  background: var(--bg-panel);
  color: var(--text);
  box-shadow: var(--shadow-float);
}
.card h3, .panel h3 { margin: 0 0 16px; }
.card p:last-child, .panel p:last-child { margin-bottom: 0; }
.panel-secondary { background: var(--bg-panel-2); color: var(--text); }
.prose { min-width: 0; overflow-wrap: break-word; }
.prose h2 { margin-top: 2.5em; scroll-margin-top: 28px; }
.prose h3 { margin-top: 1.8em; }
.prose li + li { margin-top: .55em; }
.prose :not(pre) > code {
  padding: .1em .3em;
  border-radius: var(--r-btn);
  background: var(--bg-panel-2);
  color: var(--text);
}
.reveal { opacity: 1; transform: none; }
html.reveal-ready .reveal:not(.shown) { opacity: 0; transform: translateY(18px); }
.reveal { transition: opacity var(--reveal-time) var(--ease), transform var(--reveal-time) var(--ease); }
.reveal.shown { opacity: 1; transform: none; }

/* 白色细导航使用独立的宽版心。 */
#site-header { position: relative; z-index: 50; }
.topbar {
  position: relative;
  z-index: 50;
  height: var(--nav-h);
  background: var(--nav-bg);
  color: var(--nav-ink);
}
.topbar-in {
  position: relative;
  max-width: min(100%, calc(1280px + var(--gutter) * 2));
  height: 100%;
  margin-inline: auto;
  padding-inline: var(--gutter);
  display: flex;
  align-items: center;
  gap: 32px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  flex-shrink: 0;
  color: inherit;
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: var(--weight-medium);
  letter-spacing: -.01em;
  text-decoration: none;
}
.brand:hover { text-decoration: none; }
.brand-mark {
  display: block;
  width: 34px;
  height: 34px;
  flex-shrink: 0;
  border-radius: var(--r-round);
}
.brand-placeholder {
  border-radius: var(--r-mark);
  background: var(--nav-mark-bg);
  color: var(--nav-ink);
  box-shadow: inset 0 0 0 1.5px var(--nav-mark-line);
}
.desktop-nav { min-width: 0; margin-left: auto; }
.navline {
  display: flex;
  align-items: center;
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: 14px;
  white-space: nowrap;
}
.navline li { display: flex; align-items: center; }
.navline li + li::before {
  content: "·";
  padding-inline: 11px;
  color: var(--nav-sep);
  font-weight: var(--weight-bold);
}
.navline a {
  position: relative;
  display: block;
  padding-block: 6px;
  color: var(--nav-ink);
  text-decoration: none;
}
.navline a:hover, .navline a[aria-current="page"] { color: var(--accent-dark); }
.navline a[aria-current="page"]::after {
  content: "";
  position: absolute;
  inset-inline: 0;
  bottom: -2px;
  height: 2px;
  border-radius: var(--r-pill);
  background: var(--accent);
  color: var(--nav-ink);
}
.header-tools { display: flex; align-items: center; gap: 10px; flex-shrink: 0; }
.language-picker { position: relative; }
.lang {
  min-height: 36px;
  padding: 6px 14px;
  border: 1px solid var(--nav-mark-line);
  border-radius: var(--r-pill);
  background: var(--clear);
  color: var(--nav-ink);
  font-size: 13px;
  white-space: nowrap;
}
.lang:hover { border-color: var(--nav-ink); }
.lang-short { display: none; }
.language-menu {
  position: absolute;
  top: calc(100% + 12px);
  right: 0;
  z-index: 56;
  min-width: 180px;
  margin: 0;
  padding: 8px;
  list-style: none;
  border: 1px solid var(--nav-mark-line);
  border-radius: var(--r-card);
  background: var(--nav-bg);
  color: var(--nav-ink);
  box-shadow: var(--shadow-float);
}
.language-menu a { display: block; min-height: 44px; padding: 10px 12px; color: var(--nav-ink); }
.language-menu a[aria-current="true"] { font-weight: var(--weight-bold); }
.menu-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  min-width: 44px;
  min-height: 44px;
  border: 1px solid var(--nav-mark-line);
  border-radius: var(--r-btn);
  background: var(--nav-bg);
  color: var(--nav-ink);
}
.menu-toggle svg { width: 22px; height: 22px; }
.mobile-drawer {
  position: absolute;
  top: var(--nav-h);
  inset-inline: 0;
  z-index: 55;
  max-height: calc(100vh - var(--nav-h));
  max-height: calc(100dvh - var(--nav-h));
  overflow-y: auto;
  overscroll-behavior: contain;
  padding: 16px var(--gutter) 24px;
  border-top: 1px solid var(--nav-mark-line);
  background: var(--nav-bg);
  color: var(--nav-ink);
}
.mobile-drawer ul { list-style: none; margin: 0; padding: 0; }
.mobile-drawer a {
  display: flex;
  align-items: center;
  width: 100%;
  min-height: 48px;
  padding: 12px 8px;
  border-bottom: 1px solid var(--nav-mark-line);
  color: var(--nav-ink);
  text-decoration: none;
}
.mobile-drawer a[aria-current] { color: var(--accent-dark); }
.drawer-label { margin: 24px 8px 6px; font-size: 13px; }
.menu-veil {
  position: fixed;
  inset: var(--nav-h) 0 0;
  z-index: 49;
  width: 100%;
  border: 0;
  background: var(--veil);
  color: var(--text);
}
.site-footer {
  margin-top: var(--section-space);
  padding-top: 64px;
  padding-bottom: 32px;
  border-top: 1px solid var(--border);
  background: var(--bg-panel);
  color: var(--text);
}
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1.25fr 1fr; gap: 40px; }
.footer-brand p { margin-top: 20px; max-width: 28em; color: var(--text-muted); font-size: 14px; }
.footer-title { margin: 0 0 18px; font-size: 15px; }
.footer-links { list-style: none; margin: 0; padding: 0; }
.footer-links li + li { margin-top: 10px; }
.footer-links a { color: var(--text-muted); font-size: 14px; }
.footer-links a:hover { color: var(--accent); }
.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 14px 28px;
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 12px;
}
.footer-bottom p { margin: 0; }
.footer-legal { display: flex; flex-wrap: wrap; gap: 20px; }
.footer-legal a { color: var(--text-muted); }

@media (max-width: 1279px) {
  .desktop-nav { display: none; }
  .header-tools { margin-left: auto; }
  .menu-toggle { display: inline-flex; }
}
@media (min-width: 1280px) {
  .mobile-drawer, .menu-veil { display: none !important; }
}
@media (max-width: 980px) {
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 768px) {
  :root { --title-size: 30px; --h2-size: 28px; --h3-size: 22px; }
  .grid-three { grid-template-columns: 1fr; }
}
@media (max-width: 640px) {
  :root { --gutter: 20px; }
  .topbar-in { gap: 16px; }
  .brand-name { display: none; }
  .lang-full { display: none; }
  .lang-short { display: inline; }
  .grid-two, .footer-grid { grid-template-columns: minmax(0, 1fr); }
  .card, .panel { padding: 22px; }
  .tilt, [data-tilt] { transform: none; rotate: none; }
  .footer-brand .brand-name { display: inline; }
  .footer-grid { gap: 32px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation: none !important;
    transition: none !important;
  }
  html.reveal-ready .reveal:not(.shown) { opacity: 1; transform: none; }
}