:root {
  --bg: #F5FAFC;
  --bg-panel: #FFFFFF;
  --bg-panel-2: #EEF4F9;
  --clear: transparent;
  --panel2-clear: rgba(238,244,249,0);
  --border: #E1E8F0;
  --border-strong: #D3DDE8;
  --toggle-off: #D6DEE8;
  --accent: #3E50D9;
  --accent-dark: #2A37A8;
  --accent-soft: rgba(62,80,217,.07);
  --accent-soft-2: rgba(62,80,217,.11);
  --accent-ring: rgba(62,80,217,.16);
  --grad-1: #B86BE3;
  --grad-2: #6C7FF0;
  --grad-3: #3E50D9;
  --accent-grad: linear-gradient(100deg,var(--grad-1) 0%,var(--grad-2) 50%,var(--grad-3) 100%);
  --text: #0E1220;
  --text-muted: #5A6478;
  --text-faint: #98A1B3;
  --on-accent: #FFFFFF;
  --success: #2FA36B;
  --warn: #C98A12;
  --error: #D2463F;
  --dot-close: #E9B6B1;
  --dot-min: #ECD6A4;
  --dot-max: #B5D9C4;
  --glow-violet: rgba(184,107,227,.12);
  --glow-sky: rgba(108,127,240,.10);
  --glow-indigo: rgba(62,80,217,.16);
  --glow-lilac: rgba(184,107,227,.14);
  --veil: rgba(14,18,32,.24);
  --shadow-near: 0 1px 2px rgba(27,44,84,.06),0 4px 12px -2px rgba(27,44,84,.06);
  --shadow-far: 0 44px 96px -34px rgba(40,64,128,.30);
  --shadow-chip: 0 1px 2px rgba(27,44,84,.04);
  --shadow-knob: 0 1px 2px rgba(14,18,32,.20);
  --shadow-btn: inset 0 1px 0 rgba(255,255,255,.22),0 8px 20px -8px rgba(62,80,217,.60);
  --shadow-btn-nav: 0 4px 12px -4px rgba(62,80,217,.50);
  --font-display: "Inter","Noto Sans SC","PingFang SC","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;
  --r-xl: 28px;
  --r-lg: 20px;
  --r-md: 16px;
  --r-sm: 12px;
  --r-xs: 9px;
  --r-code: 8px;
  --r-input: 10px;
  --r-pill: 999px;
  --r-circle: 50%;
  --gutter: 40px;
  --content-width: 1200px;
  --reading-width: 820px;
  --header-width: 1280px;
  --header-height: 68px;
  --section-space: 96px;
  --ease: 200ms ease;
  --reveal-time: 600ms;
  --cycle-time: 8s;
}
*,*::before,*::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
html.nav-open { overflow: hidden; }
body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--text);
  background:
    radial-gradient(900px 540px at 10% -90px,var(--glow-violet),var(--clear) 70%),
    radial-gradient(820px 520px at 94% -140px,var(--glow-sky),var(--clear) 70%),
    var(--bg);
  background-repeat: no-repeat;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
[hidden] { display: none !important; }
img,svg { max-width: 100%; vertical-align: middle; }
img { height: auto; }
button,input,select,textarea { font: inherit; }
button { cursor: pointer; }
button,a { -webkit-tap-highlight-color: var(--accent-ring); }
a { color: var(--accent); text-underline-offset: .2em; }
a:hover { color: var(--accent-dark); }
a:focus-visible,button:focus-visible,summary:focus-visible,[tabindex]:focus-visible {
  outline: 2px solid var(--accent); outline-offset: 3px;
}
h1,h2,h3,h4 { font-family: var(--font-display); color: var(--text); text-wrap: balance; overflow-wrap: break-word; }
h1 { font-size: clamp(34px,calc(2.2vw + 16px),48px); font-weight: 400; line-height: 1.15; letter-spacing: -.01em; }
h2 { font-size: clamp(26px,3vw,32px); font-weight: 400; line-height: 1.3; letter-spacing: -.005em; }
h3 { font-size: 21px; font-weight: 500; line-height: 1.45; }
p { margin-top: 0; }
code,kbd,pre,.mono { font-family: var(--font-mono); }
code { overflow-wrap: anywhere; font-size: .9em; }
pre {
  max-width: 100%; min-width: 0; overflow-x: auto; margin: 20px 0;
  padding: 20px; border: 1px solid var(--border); border-radius: var(--r-md);
  background: var(--bg-panel-2); color: var(--text); font-size: 13px; line-height: 1.8;
}
pre code { white-space: pre; overflow-wrap: normal; font-size: inherit; }
:where(section,article,aside,main,nav,div,li) { min-width: 0; }
:where(h2,h3,[id]) { scroll-margin-top: 24px; }
.wrap,.shell { width: 100%; max-width: calc(var(--content-width) + var(--gutter) * 2); margin-inline: auto; padding-inline: var(--gutter); }
.shell { max-width: 1280px; }
.reading { max-width: calc(var(--reading-width) + var(--gutter) * 2); }
.section { padding-top: var(--section-space); padding-bottom: var(--section-space); }
.surface-white { background: var(--bg-panel); color: var(--text); }
.surface-blue { background: var(--bg-panel-2); color: var(--text); }
.decorated { position: relative; overflow-x: clip; }
.section-heading { max-width: 760px; margin: 0 auto 40px; text-align: center; }
.section-heading p { color: var(--text-muted); }
.section-heading h2 { margin: 16px 0 10px; }
.keep { white-space: nowrap; }
.muted { color: var(--text-muted); }
.grid { display: grid; gap: 24px; }
.grid-two { grid-template-columns: repeat(2,minmax(0,1fr)); }
.grid-three { grid-template-columns: repeat(3,minmax(0,1fr)); }
.card,.panel {
  padding: 28px; border: 1px solid var(--border); border-radius: var(--r-lg);
  background: var(--bg-panel); color: var(--text); box-shadow: var(--shadow-near);
}
.panel { border-radius: var(--r-xl); }
.card h3 { margin-top: 0; }
.card p:last-child { margin-bottom: 0; }
.prose { min-width: 0; }
.prose h2 { margin-top: 2.2em; }
.prose h3 { margin-top: 1.8em; }
.prose p,.prose li { color: var(--text-muted); }
.prose strong { color: var(--text); }
.prose li + li { margin-top: .5em; }
.prose :not(pre) > code {
  background: var(--bg-panel-2); color: var(--text);
  padding: .12em .35em; border-radius: var(--r-code);
}
.btn,.btn-nav {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  min-height: 48px; padding: 0 24px; border: 1px solid var(--clear);
  border-radius: var(--r-sm); font-size: 15.5px; font-weight: 500; line-height: 1.4;
  text-align: center; text-decoration: none;
  transition: transform var(--ease),border-color var(--ease),color var(--ease),background-color var(--ease);
}
.btn svg,.btn-nav svg { width: 18px; height: 18px; flex-shrink: 0; fill: none; stroke: currentColor; stroke-width: 1.9; stroke-linecap: round; stroke-linejoin: round; }
.btn-primary { background: var(--accent-grad); color: var(--on-accent); box-shadow: var(--shadow-btn); }
.btn-primary:hover,.btn-primary.is-hover { color: var(--on-accent); transform: translateY(-1px); }
.btn-primary:active { transform: translateY(1px); }
.btn-ghost { background: var(--bg-panel); color: var(--text); border-color: var(--border); box-shadow: var(--shadow-chip); }
.btn-ghost:hover,.btn-ghost.is-hover { border-color: var(--border-strong); color: var(--accent); }
.btn:disabled,.btn[aria-disabled="true"] { background: var(--bg-panel-2); color: var(--text-muted); box-shadow: none; border-color: var(--border); cursor: not-allowed; transform: none; }
.btn.is-focus { outline: 2px solid var(--accent); outline-offset: 3px; }
.cta-row { display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; margin-top: 26px; }
.topbar,#site-header { position: relative; z-index: 50; }
.topbar-inner {
  position: relative; width: 100%; max-width: min(100%,calc(var(--header-width) + var(--gutter) * 2));
  padding-inline: var(--gutter); margin-inline: auto; height: var(--header-height);
  display: flex; align-items: center; gap: 24px;
}
.brand { display: inline-flex; align-items: center; gap: 10px; margin-right: auto; flex-shrink: 0; text-decoration: none; color: var(--text); font-size: 17px; font-weight: 600; line-height: 1.4; letter-spacing: -.005em; }
.brand:hover { color: var(--text); }
.brand img { width: 32px; height: 32px; flex-shrink: 0; }
.nav { min-width: 0; }
.nav ul { display: flex; align-items: center; gap: 2px; list-style: none; margin: 0; padding: 0; }
.nav a {
  display: inline-flex; align-items: center; justify-content: center; gap: 7px;
  min-height: 36px; padding: 0 12px; border-radius: var(--r-pill);
  font-size: 14.5px; white-space: nowrap; color: var(--text-muted); text-decoration: none;
  transition: color var(--ease),background-color var(--ease);
}
.nav svg,.lang svg,.mobile-drawer svg,.menu-toggle svg {
  width: 16px; height: 16px; flex-shrink: 0; fill: none; stroke: currentColor;
  stroke-width: 1.7; stroke-linecap: round; stroke-linejoin: round;
}
.nav a:hover { background: var(--bg-panel); color: var(--text); }
.nav a[aria-current="page"] { background: var(--accent-soft); color: var(--accent); }
.tools { display: flex; align-items: center; gap: 10px; flex-shrink: 0; }
.language-box { position: relative; }
.lang {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px; min-height: 36px;
  padding: 0 12px; border: 1px solid var(--border); border-radius: var(--r-pill);
  background: var(--bg-panel); color: var(--text-muted); font-size: 14px; white-space: nowrap;
}
.lang:hover { border-color: var(--border-strong); color: var(--text); }
.lang-short { display: none; }
.lang-caret { font-size: 11px; color: var(--text-muted); }
.language-menu {
  position: absolute; top: calc(100% + 10px); right: 0; width: 190px; padding: 8px;
  background: var(--bg-panel); color: var(--text); border: 1px solid var(--border);
  border-radius: var(--r-md); box-shadow: var(--shadow-near),var(--shadow-far); z-index: 4;
}
.language-menu a { display: flex; align-items: center; min-height: 44px; padding: 8px 12px; border-radius: var(--r-xs); color: var(--text-muted); text-decoration: none; }
.language-menu a:hover,.language-menu a[aria-current="true"] { background: var(--accent-soft); color: var(--accent); }
.btn-nav { min-height: 38px; padding-inline: 18px; background: var(--accent); color: var(--on-accent); font-size: 14px; box-shadow: var(--shadow-btn-nav); white-space: nowrap; }
.btn-nav:hover { background: var(--accent-dark); color: var(--on-accent); }
.menu-toggle { display: none; align-items: center; justify-content: center; min-width: 44px; min-height: 44px; padding: 0; border: 1px solid var(--border); border-radius: var(--r-sm); background: var(--bg-panel); color: var(--text); }
.menu-toggle svg { width: 22px; height: 22px; }
.mobile-drawer {
  position: absolute; top: var(--header-height); left: 0; right: 0; z-index: 3;
  padding: 20px var(--gutter); max-height: calc(100dvh - var(--header-height)); overflow-y: auto;
  overscroll-behavior: contain; border-bottom: 1px solid var(--border);
  background: var(--bg-panel); color: var(--text); box-shadow: var(--shadow-near);
}
.mobile-drawer ul { list-style: none; margin: 0; padding: 0; }
.mobile-drawer a { display: flex; width: 100%; align-items: center; gap: 12px; min-height: 48px; padding: 12px; color: var(--text-muted); text-decoration: none; border-radius: var(--r-xs); }
.mobile-drawer a:hover,.mobile-drawer a[aria-current] { background: var(--accent-soft); color: var(--accent); }
.drawer-languages { border-top: 1px solid var(--border); margin-top: 12px; padding-top: 12px; }
.nav-veil { position: fixed; inset: var(--header-height) 0 0; z-index: 1; border: 0; padding: 0; background: var(--veil); color: var(--text); cursor: default; }
.hero { position: relative; overflow: hidden; background: linear-gradient(180deg,var(--clear) 0%,var(--clear) 58%,var(--bg-panel-2) 100%); color: var(--text); }
.hero-glow {
  position: absolute; z-index: 0; right: -180px; bottom: 60px; width: 960px; height: 620px; pointer-events: none;
  background: radial-gradient(closest-side at 58% 56%,var(--glow-indigo),var(--clear)),radial-gradient(closest-side at 34% 38%,var(--glow-lilac),var(--clear));
}
.hero-copy { position: relative; z-index: 2; display: flex; flex-direction: column; align-items: center; text-align: center; padding-top: 32px; }
.badge { display: inline-flex; align-items: center; gap: 9px; max-width: 100%; padding: 5px 14px 5px 11px; border: 1px solid var(--border); border-radius: var(--r-pill); background: var(--bg-panel); color: var(--text-muted); box-shadow: var(--shadow-chip); font-size: 13px; line-height: 18px; }
.hero-copy .badge { margin: 1em 0; }
.badge-dot { width: 8px; height: 8px; flex-shrink: 0; border-radius: var(--r-circle); background: var(--accent); box-shadow: 0 0 0 3px var(--accent-ring); }
.badge-sep { color: var(--text-muted); }
.hero h1 { margin: 20px 0 0; font-size: clamp(30px,calc(2.2vw + 16px),48px); font-weight: 400; line-height: 1.15; }
.hero h1 .line { display: block; }
.grad { background: var(--accent-grad); color: var(--clear); background-clip: text; -webkit-background-clip: text; -webkit-text-fill-color: var(--clear); }
.lead { margin: 18px 0 0; max-width: 760px; font-size: 16px; line-height: 26px; color: var(--text-muted); }
.lead strong { color: var(--text); font-weight: 600; }
.platforms { display: flex; flex-wrap: wrap; justify-content: center; gap: 8px; margin: 18px 0 0; padding: 0; list-style: none; }
.platforms a { display: inline-flex; align-items: center; justify-content: center; gap: 7px; min-height: 32px; padding: 0 13px 0 11px; border: 1px solid var(--border); border-radius: var(--r-pill); background: var(--bg-panel); color: var(--text-muted); font-size: 13px; text-decoration: none; box-shadow: var(--shadow-chip); }
.platforms svg { width: 14px; height: 14px; flex-shrink: 0; color: var(--text); }
.platforms a:hover { border-color: var(--accent-ring); color: var(--accent); }
.platforms a:hover svg { color: var(--accent); }
.eyebrow { display: inline-flex; align-items: center; gap: 8px; font-size: 13px; line-height: 18px; font-weight: 500; letter-spacing: .04em; color: var(--accent); }
.eyebrow::before { content: ""; width: 6px; height: 6px; flex-shrink: 0; border-radius: var(--r-circle); background: var(--accent); }
.next { background: var(--bg-panel-2); color: var(--text); padding-top: 14px; padding-bottom: 96px; text-align: center; }
.next h2 { margin: 16px 0 10px; }
.next p { max-width: 640px; margin-inline: auto; font-size: 16px; color: var(--text-muted); }
.fact-strip { background: var(--bg-panel-2); color: var(--text-muted); font-family: var(--font-mono); font-size: 12px; text-align: center; padding: 16px var(--gutter); overflow-x: auto; white-space: nowrap; }
.site-footer { background: var(--bg-panel); color: var(--text-muted); border-top: 1px solid var(--border); padding-top: 64px; padding-bottom: 28px; }
.footer-grid { display: grid; grid-template-columns: 1.5fr 1fr 1.4fr 1fr; gap: 40px; }
.footer-brand p { margin-top: 20px; max-width: 320px; font-size: 14px; }
.site-footer h2 { font-family: var(--font-body); font-size: 14px; font-weight: 600; margin: 0 0 16px; }
.site-footer ul { list-style: none; padding: 0; margin: 0; }
.site-footer li { margin-bottom: 9px; font-size: 13px; }
.site-footer a:not(.brand) { color: var(--text-muted); text-decoration: none; }
.site-footer a:hover { color: var(--accent); }
.footer-bottom { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px; margin-top: 48px; padding-top: 24px; border-top: 1px solid var(--border); font-size: 13px; }
.reveal { opacity: 1; transform: none; }
.reveal-ready .reveal:not(.shown) { opacity: 0; transform: translateY(16px); }
.reveal-ready .reveal { transition: opacity var(--reveal-time) ease,transform var(--reveal-time) ease; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; border: 0; }
@media (max-width: 1280px) {
  .topbar-inner { gap: 16px; }
  .nav a { padding-inline: 9px; font-size: 14px; }
  html:not([lang="zh-CN"]):not([lang="zh-TW"]) .nav { display: none; }
  html:not([lang="zh-CN"]):not([lang="zh-TW"]) .menu-toggle { display: inline-flex; }
}
@media (max-width: 1180px) { .lang-text { display: none; } .lang-short { display: inline; } }
@media (max-width: 1080px) {
  .nav { display: none; }
  .menu-toggle { display: inline-flex; }
  .tools { margin-left: auto; }
  .footer-grid { grid-template-columns: repeat(2,minmax(0,1fr)); }
}
@media (min-width: 1281px) { .mobile-drawer,.nav-veil { display: none; } }
@media (max-width: 768px) {
  :root { --gutter: 20px; --section-space: 64px; }
  h1,.hero h1 { font-size: clamp(24px,4vw,30px); }
  .hero-copy { padding-top: 24px; }
  .lead { font-size: 15px; line-height: 24px; }
  .grid-three { grid-template-columns: 1fr; }
  .next h2 { font-size: 24px; }
}
@media (max-width: 640px) {
  :root { --gutter: 16px; }
  .tilt,[data-tilt] { transform: none !important; }
  .topbar-inner { gap: 8px; }
  .tools { gap: 6px; margin-left: auto; }
  .brand { font-size: 15px; gap: 7px; }
  .brand img { width: 28px; height: 28px; }
  .tools .btn-nav { display: none; }
  .lang { padding-inline: 9px; min-height: 40px; }
  .lang-text { display: none; }
  .lang-short { display: inline; }
  .grid-two,.footer-grid { grid-template-columns: 1fr; }
  .card,.panel { padding: 20px; }
  .hero .badge { font-size: 11px; gap: 7px; }
  .platforms { gap: 6px; flex-direction: row; }
  .platforms a { padding-inline: 10px; }
  .keep { white-space: normal; }
  .footer-grid { gap: 28px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *,*::before,*::after { transition: none !important; animation: none !important; }
  .reveal-ready .reveal:not(.shown) { opacity: 1; transform: none; }
}