:root {
  --bg:#F4F4F1;
  --panel:#FFFFFF;
  --panel-2:#EBEBE7;
  --border:#DEDDD8;
  --accent:#245FCC;
  --accent-dark:#18469E;
  --accent-soft:rgba(36,95,204,.10);
  --text:#1A1A19;
  --muted:#64635F;
  --success:#2F8A5B;
  --warn:#B57A1E;
  --error:#C4473B;
  --success-ink:#246B46;
  --warn-ink:#805514;
  --coral:#E8775A;
  --stage:#1C1B1A;
  --stage-2:#262524;
  --stage-line:#3A3936;
  --on-stage:#F4F4F1;
  --on-stage-muted:#A6A5A0;
  --veil:rgba(26,26,25,.35);
  --transparent: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 GB","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;
  --weight-normal:400;
  --weight-medium:500;
  --weight-strong:600;
  --fs-10:10px;
  --fs-11:11px;
  --fs-115:11.5px;
  --fs-12:12px;
  --fs-125:12.5px;
  --fs-13:13px;
  --fs-135:13.5px;
  --fs-14:14px;
  --fs-145:14.5px;
  --fs-15:15px;
  --fs-155:15.5px;
  --fs-16:16px;
  --fs-18:18px;
  --fs-20:20px;
  --fs-22:22px;
  --fs-24:24px;
  --fs-h1:clamp(34px,3.4vw,48px);
  --fs-h2:clamp(26px,2.6vw,36px);
  --fs-h3:clamp(20px,2vw,24px);
  --fs-h1-mobile:clamp(24px,6.5vw,30px);
  --line-body:1.6;
  --line-copy:1.8;
  --line-title:1.16;
  --tracking-title:-.015em;
  --r-xl:28px;
  --r-lg:24px;
  --r-card:20px;
  --r-md:14px;
  --r-sm:10px;
  --r-xs:7px;
  --r-focus:6px;
  --r-line:2px;
  --r-pill:999px;
  --r-circle:50%;
  --r-logo:30%;
  --r-phone:40px;
  --r-screen:33px;
  --r-sidekey:0 3px 3px 0;
  --shadow-card:0 1px 2px rgba(26,26,25,.04),0 10px 24px -14px rgba(26,26,25,.14);
  --shadow-win:0 1px 2px rgba(26,26,25,.04),0 14px 30px -18px rgba(26,26,25,.12),0 40px 90px -36px rgba(26,26,25,.22);
  --shadow-phone:0 2px 4px rgba(26,26,25,.10),0 20px 40px -20px rgba(26,26,25,.30),0 48px 90px -30px rgba(26,26,25,.42);
  --shadow-knob:0 1px 2px rgba(26,26,25,.22);
  --shadow-accent:0 14px 28px -12px rgba(36,95,204,.55);
  --shadow-btn:0 1px 0 rgba(255,255,255,.18) inset,0 8px 18px -10px rgba(24,70,158,.6);
  --ease:cubic-bezier(.22,.7,.2,1);
  --gutter:64px;
  --header-h:73px;
  --peek:44px;
}
*,*::before,*::after { box-sizing:border-box; }
html { -webkit-text-size-adjust:100%; scroll-behavior:smooth; scroll-padding-top:24px; }
html.nav-open { overflow:hidden; }
body {
  margin:0; background:var(--bg); color:var(--text);
  font-family:var(--font-body); font-size:var(--fs-16); line-height:var(--line-body);
  -webkit-font-smoothing:antialiased;
}
[hidden] { display:none !important; }
img,svg { display:block; max-width:100%; }
img { height:auto; }
svg { flex-shrink:0; }
button,input,select,textarea { font:inherit; }
button,a,input,summary { -webkit-tap-highlight-color:var(--transparent); }
button { cursor:pointer; }
button:disabled { cursor:not-allowed; }
a { color:var(--accent); text-underline-offset:4px; }
a:hover { color:var(--accent-dark); }
:focus-visible { outline:2px solid var(--accent); outline-offset:3px; border-radius:var(--r-focus); }
::selection { background:var(--accent); color:var(--panel); }
h1,h2,h3,h4 { font-family:var(--font-display); font-weight:var(--weight-normal); text-wrap:balance; }
h1 { font-size:var(--fs-h1); line-height:var(--line-title); letter-spacing:var(--tracking-title); }
h2 { font-size:var(--fs-h2); line-height:1.25; letter-spacing:-.01em; }
h3 { font-size:var(--fs-h3); line-height:1.35; }
p { margin:0 0 1.25em; }
strong { font-weight:var(--weight-strong); }
small { font-size:var(--fs-13); }
code,kbd,pre { font-family:var(--font-mono); }
code { overflow-wrap:anywhere; }
pre {
  max-width:100%; min-width:0; overflow-x:auto; padding:20px;
  background:var(--panel-2); color:var(--text);
  border:1px solid var(--border); border-radius:var(--r-md);
  font-size:var(--fs-13); line-height:1.8; 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:32px; }
section[id],h2[id],h3[id] { scroll-margin-top:24px; }
.wrap { width:100%; max-width:1440px; margin-inline:auto; padding-inline:var(--gutter); }
.reading { width:100%; max-width:960px; margin-inline:auto; padding-inline:var(--gutter); }
.section { padding-top:96px; padding-bottom:104px; }
.section--white { background:var(--panel); color:var(--text); }
.section-head { max-width:680px; margin-bottom:40px; }
.section-head h2 { margin:12px 0 16px; }
.eyebrow { font-size:var(--fs-13); color:var(--muted); margin:0; }
.muted { color:var(--muted); }
.keep { white-space:nowrap; }
.grid { display:grid; grid-template-columns:repeat(3,minmax(0,1fr)); gap:24px; }
.grid > *, .hero__main > *, .footer-grid > *, .feature-panel > *, .prose > *, .prose div { min-width:0; }
.stack { display:grid; gap:24px; }
.actions { display:flex; flex-wrap:wrap; align-items:center; gap:12px; }
.btn {
  display:inline-flex; align-items:center; justify-content:center; gap:10px;
  min-height:52px; padding:12px 24px; max-width:100%;
  border:1px solid var(--transparent); border-radius:var(--r-md);
  font-family:var(--font-body); font-size:var(--fs-16); font-weight:var(--weight-medium);
  line-height:1.5; text-decoration:none; text-align:center;
  transition:background-color .2s ease,border-color .2s ease,transform .2s ease;
}
.btn svg { width:18px; height:18px; fill:none; stroke:currentColor; stroke-width:1.8; stroke-linecap:round; stroke-linejoin:round; transition:transform .25s var(--ease); }
.btn--primary { background:var(--accent); color:var(--panel); box-shadow:var(--shadow-btn); }
.btn--primary:hover,.btn--primary.is-hover { background:var(--accent-dark); color:var(--panel); }
.btn--primary:hover svg { transform:translateX(3px); }
.btn--ghost { background:var(--panel); color:var(--text); border-color:var(--border); }
.btn--ghost:hover,.btn--ghost.is-hover { border-color:var(--muted); color:var(--text); }
.btn:active,.btn.is-pressed { transform:translateY(1px); }
.btn:disabled,.btn[aria-disabled="true"] { background:var(--panel-2); color:var(--muted); border-color:var(--border); box-shadow:none; }
.btn[aria-disabled="true"] { pointer-events:none; }
.btn.is-focus { outline:2px solid var(--accent); outline-offset:3px; }
.btn--small { min-height:44px; padding:9px 18px; font-size:var(--fs-14); }
.panel,.card {
  min-width:0; padding:28px; border:1px solid var(--border);
  border-radius:var(--r-xl); background:var(--panel); color:var(--text); box-shadow:var(--shadow-card);
}
.card h3 { margin:0 0 12px; }
.card p:last-child { margin-bottom:0; }
.prose { min-width:0; line-height:var(--line-copy); }
.prose h2 { margin:64px 0 24px; }
.prose h3 { margin:36px 0 16px; }
.prose li { margin-block:8px; }
.prose :not(pre) > code { padding:2px 5px; border-radius:var(--r-xs); background:var(--panel-2); color:var(--text); font-size:.9em; }
.prose img { max-width:100%; }
.reveal { transition:opacity .6s var(--ease),transform .6s var(--ease); }
.reveal.reveal-pending:not(.shown) { opacity:0; transform:translateY(12px); }
.reveal.shown { opacity:1; transform:none; }
.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:absolute; top:8px; left:16px; z-index:30; }
.skip-link:not(:focus) {
  width:1px; height:1px; min-height:0; padding:0; margin:-1px;
  overflow:hidden; clip-path:inset(50%); white-space:nowrap; border:0;
}
.topbar { position:relative; z-index:20; background:var(--panel); color:var(--text); border-bottom:1px solid var(--border); }
.topbar__inner {
  position:relative; display:flex; align-items:center; height:72px; gap:32px;
  width:100%; max-width:min(100%,calc(1280px + var(--gutter) * 2));
  margin-inline:auto; padding-inline:var(--gutter);
}
.brand { display:inline-flex; align-items:center; gap:11px; margin-right:auto; flex-shrink:0; color:var(--text); text-decoration:none; }
.brand:hover { color:var(--text); }
.brand__mark { width:34px; height:34px; flex-shrink:0; border-radius:var(--r-logo); }
.brand__name { font-family:var(--font-display); font-size:var(--fs-18); font-weight:var(--weight-medium); letter-spacing:-.01em; }
.brand__name span { margin-left:2px; color:var(--muted); font-weight:var(--weight-normal); }
.tabs { position:relative; height:72px; min-width:0; }
.tabs__list { display:flex; align-items:center; list-style:none; margin:0; padding:0; height:100%; }
.tabs__list li { flex-shrink:0; height:100%; }
.tabs__list a {
  position:relative; display:flex; align-items:center; justify-content:center;
  height:100%; padding-inline:14px; white-space:nowrap;
  color:var(--muted); font-size:var(--fs-145); text-decoration:none; transition:color .2s ease;
}
.tabs__list li:nth-child(1),.tabs__list li:nth-child(4) { width:64px; }
.tabs__list li:nth-child(2) { width:80px; }
.tabs__list li:nth-child(3),.tabs__list li:nth-child(6) { width:96px; }
.tabs__list li:nth-child(5) { width:112px; }
.tabs__list a:hover,.tabs__list a[aria-current="page"] { color:var(--text); }
.tabs__bar {
  position:absolute; left:0; bottom:-1px; width:100px; height:2px;
  border-radius:var(--r-line); background:var(--accent); color:var(--panel);
  transform-origin:0 50%; transform:translateX(var(--tab-x,0px)) scaleX(var(--tab-scale,0));
  transition:transform .38s var(--ease); pointer-events:none;
}
.tabs[data-active="index"] { --tab-x:14px; --tab-scale:.36; }
.tabs[data-active="download"] { --tab-x:78px; --tab-scale:.52; }
.tabs[data-active="tutorial"] { --tab-x:158px; --tab-scale:.68; }
.tabs[data-active="faq"] { --tab-x:254px; --tab-scale:.36; }
.tabs[data-active="compare"] { --tab-x:318px; --tab-scale:.84; }
.tabs[data-active="deepdoc"] { --tab-x:430px; --tab-scale:.68; }
.tabs:has(li:nth-child(1) a:is(:hover,:focus-visible)) { --tab-x:14px; --tab-scale:.36; }
.tabs:has(li:nth-child(2) a:is(:hover,:focus-visible)) { --tab-x:78px; --tab-scale:.52; }
.tabs:has(li:nth-child(3) a:is(:hover,:focus-visible)) { --tab-x:158px; --tab-scale:.68; }
.tabs:has(li:nth-child(4) a:is(:hover,:focus-visible)) { --tab-x:254px; --tab-scale:.36; }
.tabs:has(li:nth-child(5) a:is(:hover,:focus-visible)) { --tab-x:318px; --tab-scale:.84; }
.tabs:has(li:nth-child(6) a:is(:hover,:focus-visible)) { --tab-x:430px; --tab-scale:.68; }
.header-tools { display:flex; align-items:center; gap:10px; flex-shrink:0; }
.language { position:relative; }
.lang {
  display:inline-flex; align-items:center; justify-content:center; gap:8px;
  min-height:36px; padding:6px 14px; border:1px solid var(--border);
  border-radius:var(--r-pill); background:var(--panel); color:var(--text);
  font-size:var(--fs-135); line-height:1.5; cursor:pointer; list-style:none;
}
.lang::-webkit-details-marker { display:none; }
.lang:hover { border-color:var(--muted); }
.lang svg { width:16px; height:16px; fill:none; stroke:var(--muted); stroke-width:1.5; }
.lang__caret { color:var(--muted); font-size:var(--fs-11); }
.lang__short { display:none; }
.language-menu {
  position:absolute; right:0; top:calc(100% + 12px); z-index:24; min-width:180px;
  padding:8px; margin:0; list-style:none; border:1px solid var(--border);
  border-radius:var(--r-md); background:var(--panel); color:var(--text); box-shadow:var(--shadow-win);
}
.language-menu a { display:flex; align-items:center; min-height:44px; padding:10px 14px; border-radius:var(--r-sm); color:var(--text); text-decoration:none; }
.language-menu a:hover,.language-menu a[aria-current="true"] { background:var(--bg); color:var(--text); }
.menu-button {
  display:none; align-items:center; justify-content:center; min-width:44px; min-height:44px;
  border:1px solid var(--border); border-radius:var(--r-sm);
  background:var(--panel); color:var(--text); text-decoration:none;
}
.menu-button svg { width:20px; height:20px; fill:none; stroke:currentColor; stroke-width:1.6; }
.mobile-drawer { display:none; }
.menu-veil { position:fixed; inset:72px 0 0; z-index:18; border:0; background:var(--veil); color:var(--text); }
.site-footer { padding-top:64px; padding-bottom:28px; border-top:1px solid var(--border); background:var(--panel); color:var(--text); }
.footer-grid { display:grid; grid-template-columns:1.4fr 1fr 1.4fr 1fr; gap:40px; }
.footer-brand p { max-width:320px; margin:20px 0 0; color:var(--muted); font-size:var(--fs-14); }
.footer-heading { margin:0 0 16px; font-size:var(--fs-14); font-weight:var(--weight-medium); }
.footer-links { list-style:none; margin:0; padding:0; display:grid; gap:10px; }
.footer-links a { color:var(--muted); font-size:var(--fs-14); text-decoration:none; }
.footer-links a:hover { color:var(--accent); text-decoration:underline; }
.footer-bottom { display:flex; flex-wrap:wrap; justify-content:space-between; gap:12px 24px; margin-top:48px; padding-top:24px; border-top:1px solid var(--border); font-size:var(--fs-13); color:var(--muted); }
.footer-bottom p { margin:0; }
.footer-legal { display:flex; flex-wrap:wrap; gap:20px; }
.footer-legal a { color:var(--muted); }
@media (max-width:1180px) {
  :root { --gutter:48px; }
  .topbar__inner { gap:20px; }
}
@media (max-width:1100px) {
  .desktop-nav { display:none; }
  .header-tools { margin-left:auto; }
  .menu-button { display:inline-flex; }
  .topbar__inner { gap:16px; }
  .mobile-drawer:not([hidden]) {
    display:block; position:absolute; z-index:23; top:72px; left:0; right:0;
    padding:16px var(--gutter) 24px; max-height:calc(100dvh - 72px);
    overflow-y:auto; overscroll-behavior:contain;
    border-bottom:1px solid var(--border); background:var(--panel); color:var(--text);
  }
  .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; color:var(--text); text-decoration:none; border-radius:var(--r-sm); }
  .mobile-drawer a:hover,.mobile-drawer a[aria-current="page"] { background:var(--bg); color:var(--text); }
  .mobile-drawer a[aria-current="page"] { box-shadow:inset 2px 0 var(--accent); }
  .mobile-drawer__label { margin:16px 12px 8px; color:var(--muted); font-size:var(--fs-12); }
  .footer-grid { grid-template-columns:repeat(2,minmax(0,1fr)); }
}
@media (max-width:768px) {
  :root { --gutter:24px; }
  h1 { font-size:var(--fs-h1-mobile); }
  .section { padding-top:64px; padding-bottom:64px; }
  .grid { grid-template-columns:minmax(0,1fr); }
  .panel,.card { padding:24px; }
}
@media (max-width:640px) {
  :root { --gutter:20px; }
  .tilt,[data-tilt] { transform:none !important; }
  .footer-grid { gap:32px 24px; }
  .footer-brand { grid-column:1/-1; }
  .brand__name { font-size:var(--fs-16); }
  .topbar__inner { gap:8px; }
  .brand { gap:8px; }
  .lang__full { display:none; }
  .lang__short { display:inline; }
  .lang { padding-inline:12px; }
  .header-tools { gap:8px; margin-left:auto; }
  .prose h2 { margin-top:44px; }
}
@media (max-width:359px) {
  :root { --gutter:16px; }
  .brand__name span { display:none; }
  .btn { padding-inline:18px; }
}
@media (prefers-reduced-motion:reduce) {
  html { scroll-behavior:auto; }
  *,*::before,*::after { animation:none !important; transition:none !important; }
  .reveal.reveal-pending:not(.shown) { opacity:1; transform:none; }
}