:root {
  --bg: #FFFFFF;
  --bg-panel: #F5F7FB;
  --bg-panel-2: #EEF2F8;
  --border: #E3E7EF;
  --accent: #1660F5;
  --accent-dark: #0A2B8F;
  --accent-bright: #4F8BFF;
  --text: #0E1530;
  --text-muted: #5A6278;
  --success: #12A36B;
  --success-ring: rgba(18,163,107,.28);
  --warn: #E0960A;
  --error: #E5484D;
  --coral: #FF6F61;
  --magenta: #E8408F;
  --hero-0: #071345;
  --hero-1: #0E2585;
  --hero-2: #1D46D8;
  --hero-3: #6E8CEE;
  --hero-4: #C3CEFA;
  --glow: rgba(60,123,255,.30);
  --glow-clear: rgba(60,123,255,0);
  --on-dark: #FFFFFF;
  --on-dark-soft: rgba(255,255,255,.84);
  --on-dark-muted: rgba(255,255,255,.64);
  --on-dark-line: rgba(255,255,255,.24);
  --on-dark-fill: rgba(255,255,255,.08);
  --on-dark-fill-2: rgba(255,255,255,.14);
  --btn-ghost-fill: rgba(195,206,250,.24);
  --btn-ghost-fill-hover: rgba(195,206,250,.36);
  --hl: rgba(110,160,255,.62);
  --page: #FBFCFF;
  --shell-highlight: rgba(255,255,255,.42);
  --shell-rim: rgba(255,255,255,.08);
  --shadow-cobalt: rgba(22,96,245,.40);
  --veil: rgba(7,19,69,.44);
  --clear: transparent;
  --t1: #0A2B8F;
  --t1-hi: #1A3DAA;
  --t1-lo: #061D66;
  --t2: #1240C0;
  --t2-hi: #2253D2;
  --t2-lo: #0B2E96;
  --t3: #1660F5;
  --t3-hi: #2E73FA;
  --t3-lo: #0E47C4;
  --t4: #2A6DFA;
  --t4-hi: #4580FC;
  --t4-lo: #1A54D6;
  --t5: #3C7BFF;
  --t5-hi: #5C92FF;
  --t5-lo: #2860E0;

  --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',ui-monospace,'SFMono-Regular',Menlo,Consolas,monospace;
  --weight-normal: 400;
  --weight-medium: 500;
  --size-xs: 12px;
  --size-sm: 14px;
  --size-body: 16px;
  --size-lead: 18px;
  --size-h1: clamp(34px,3.2vw,48px);
  --size-h2: clamp(28px,3.4vw,44px);
  --size-h3: clamp(20px,2vw,26px);
  --line-body: 1.7;
  --line-heading: 1.16;
  --tracking-heading: -.012em;
  --r-panel: 32px;
  --r-card: 28px;
  --r-page: 18px;
  --r-field: 10px;
  --r-chip: 10px;
  --r-small: 4px;
  --r-pill: 999px;
  --r-round: 50%;
  --gutter: 32px;
  --content-width: 1200px;
  --reading-width: 820px;
  --header-width: 1280px;
  --header-height: 68px;
  --section-space: clamp(64px,8vw,120px);
  --motion-fast: .2s;
  --motion-reveal: .6s;
  --field-h: 760px;
  --card-w: clamp(300px,22.2vw,380px);
  --card-h: 384px;
  --card-gap: clamp(18px,1.7vw,32px);
  --lift: 22px;
}

*, *::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(--size-body);
  font-weight: var(--weight-normal);
  line-height: var(--line-body);
  -webkit-font-smoothing: antialiased;
}
[hidden] { display: none !important; }
a { color: inherit; text-decoration: none; }
button, input, select, textarea { font: inherit; }
button { cursor: pointer; }
button, input, select, textarea { max-width: 100%; }
button:disabled { cursor: not-allowed; }
img, svg, video { max-width: 100%; vertical-align: middle; }
img { height: auto; }
svg, .dot, .sb-dot, .icon { flex-shrink: 0; }
h1, h2, h3, h4, p, figure, blockquote { margin: 0; }
h1, h2, h3 {
  font-family: var(--font-display);
  font-weight: var(--weight-normal);
  line-height: var(--line-heading);
  letter-spacing: var(--tracking-heading);
  text-wrap: balance;
}
h1 { font-size: var(--size-h1); }
h2 { font-size: var(--size-h2); }
h3 { font-size: var(--size-h3); }
ul, ol { padding-inline-start: 1.4em; }
dl, dd { margin: 0; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; }
::selection { background: var(--hero-4); color: var(--text); }
.wrap {
  width: 100%;
  max-width: calc(var(--content-width) + var(--gutter) * 2);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.reading { max-width: calc(var(--reading-width) + var(--gutter) * 2); }
.section { padding-top: var(--section-space); padding-bottom: var(--section-space); }
.section + .section { padding-top: 0; }
.stack > * + * { margin-top: 20px; }
.grid { display: grid; grid-template-columns: repeat(3,minmax(0,1fr)); gap: 24px; }
.grid > *, .feature-panel > *, .footer-grid > *, .topbar-inner > *, .prose * { min-width: 0; }
.nowrap { white-space: nowrap; }
.muted { color: var(--text-muted); }
.small { font-size: var(--size-sm); }
.mono { font-family: var(--font-mono); }
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}
.prose { line-height: 1.85; overflow-wrap: break-word; }
.prose > * + * { margin-top: 22px; }
.prose h2 { margin-top: 64px; }
.prose h3 { margin-top: 36px; }
.prose a { color: var(--accent-dark); text-decoration: underline; text-underline-offset: 4px; }
code {
  font-family: var(--font-mono);
  font-size: .88em;
  overflow-wrap: anywhere;
  color: var(--accent-dark);
  background: var(--bg-panel);
  border-radius: var(--r-small);
  padding: .12em .3em;
}
pre {
  max-width: 100%;
  min-width: 0;
  overflow-x: auto;
  padding: 24px;
  border: 1px solid var(--border);
  border-radius: var(--r-page);
  background: var(--bg-panel);
  color: var(--text);
  font-family: var(--font-mono);
  font-size: var(--size-sm);
  line-height: 1.7;
  tab-size: 2;
}
pre code { padding: 0; background: var(--clear); color: inherit; white-space: pre; overflow-wrap: normal; }
.panel, .surface-card {
  border: 1px solid var(--border);
  border-radius: var(--r-card);
  padding: 28px;
  background: var(--bg-panel);
  color: var(--text);
}
.panel { border-radius: var(--r-panel); }
.surface-card h3 { margin-bottom: 14px; }
.surface-card p { color: var(--text-muted); }
.section-heading { display: flex; justify-content: space-between; align-items: flex-end; gap: 24px; margin-bottom: 36px; }
.section-heading > * { min-width: 0; }
.section-heading h2 span { display: block; }
.gradient-title {
  background: linear-gradient(100deg,var(--accent-dark),var(--magenta));
  color: var(--accent-dark);
  background-clip: text;
  -webkit-background-clip: text;
  -webkit-text-fill-color: var(--clear);
  padding-bottom: .1em;
}

.btn {
  display: inline-flex;
  justify-content: center;
  align-items: center;
  gap: 8px;
  min-height: 48px;
  padding: 10px 26px;
  border: 1px solid var(--clear);
  border-radius: var(--r-pill);
  background: var(--accent);
  color: var(--on-dark);
  font-size: var(--size-body);
  font-weight: var(--weight-medium);
  letter-spacing: -.005em;
  line-height: 1.4;
  text-align: center;
  transition: background-color var(--motion-fast), border-color var(--motion-fast);
}
.btn svg { width: 18px; height: 18px; }
.btn:hover, .btn.is-hover { background: var(--accent-dark); color: var(--on-dark); }
.btn:active, .btn.is-active { background: var(--hero-0); color: var(--on-dark); }
.btn:disabled, .btn[aria-disabled="true"] { background: var(--bg-panel-2); color: var(--text-muted); border-color: var(--border); }
.btn-outline { border-color: var(--border); background: var(--bg); color: var(--accent-dark); }
.btn-outline:hover { background: var(--bg-panel-2); color: var(--accent-dark); border-color: var(--accent); }
.btn-primary { background: var(--bg); color: var(--text); }
.btn-primary svg { color: var(--accent); }
.btn-primary:hover { background: var(--bg-panel); color: var(--text); }
.btn-ghost { background: var(--btn-ghost-fill); color: var(--on-dark); border-color: var(--on-dark-line); }
.btn-ghost:hover { background: var(--btn-ghost-fill-hover); color: var(--on-dark); }
.button-row { display: flex; flex-wrap: wrap; align-items: center; gap: 12px; }

.topbar { position: relative; z-index: 50; background: var(--bg); color: var(--text); }
.topbar-inner {
  position: relative;
  max-width: min(100%,calc(var(--header-width) + var(--gutter) * 2));
  min-height: var(--header-height);
  margin-inline: auto;
  padding-inline: var(--gutter);
  display: flex;
  align-items: center;
  gap: 44px;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
  font-size: var(--size-body);
  font-weight: var(--weight-medium);
  letter-spacing: -.005em;
  white-space: nowrap;
  flex-shrink: 0;
}
.brand-mark { width: 32px; height: 32px; flex: none; }
.desktop-nav { min-width: 0; align-self: stretch; display: flex; }
.tabs {
  display: flex;
  align-items: center;
  list-style: none;
  margin: 0;
  padding: 0;
  gap: 2px;
  align-self: stretch;
}
.tabs li { display: flex; height: 100%; }
.tab {
  position: relative;
  display: flex;
  align-items: center;
  min-height: 44px;
  padding: 0 14px;
  font-size: 15px;
  color: var(--text-muted);
  white-space: nowrap;
  transition: color var(--motion-fast);
}
.tab:hover, .tab[aria-current="page"] { color: var(--text); }
.tab[aria-current="page"]::after {
  content: "";
  position: absolute;
  left: 14px;
  right: 14px;
  bottom: 12px;
  height: 3px;
  border-radius: var(--r-pill);
  background: var(--accent);
}
.header-tools { margin-left: auto; display: flex; align-items: center; gap: 8px; flex-shrink: 0; }
.language-picker { position: relative; }
.lang {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 36px;
  padding: 5px 14px;
  border: 1px solid var(--border);
  border-radius: var(--r-pill);
  background: var(--bg-panel);
  color: var(--text);
  font-family: var(--font-body);
  font-size: var(--size-sm);
  white-space: nowrap;
}
.lang svg { width: 16px; height: 16px; }
.lang-caret { font-size: 11px; }
.lang-short { display: none; }
.language-menu {
  position: absolute;
  z-index: 4;
  top: calc(100% + 10px);
  right: 0;
  width: 190px;
  padding: 8px;
  list-style: none;
  border: 1px solid var(--border);
  border-radius: var(--r-page);
  background: var(--bg);
  color: var(--text);
}
.language-menu a { display: flex; align-items: center; min-height: 44px; padding: 8px 14px; border-radius: var(--r-chip); }
.language-menu a:hover, .language-menu a[aria-current="true"] { background: var(--bg-panel); color: var(--accent-dark); }
.menu-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  min-width: 44px;
  min-height: 44px;
  border: 1px solid var(--border);
  border-radius: var(--r-pill);
  background: var(--bg-panel);
  color: var(--text);
}
.menu-toggle svg { width: 20px; height: 20px; }
.menu-veil { position: fixed; inset: var(--header-height) 0 0; z-index: 1; border: 0; background: var(--veil); color: var(--on-dark); }
.mobile-drawer {
  position: absolute;
  z-index: 3;
  top: 100%;
  left: 0;
  right: 0;
  padding: 16px var(--gutter) 24px;
  max-height: calc(100dvh - var(--header-height));
  overflow-y: auto;
  overscroll-behavior: contain;
  background: var(--bg);
  color: var(--text);
  border-bottom: 1px solid var(--border);
}
.mobile-drawer ul { list-style: none; padding: 0; margin: 0; }
.mobile-drawer a { display: flex; align-items: center; width: 100%; min-height: 46px; padding: 10px 14px; border-radius: var(--r-chip); }
.mobile-drawer a:hover, .mobile-drawer a[aria-current] { background: var(--bg-panel); color: var(--accent-dark); }
.drawer-languages { margin-top: 16px !important; padding-top: 16px !important; border-top: 1px solid var(--border); }
.stage .topbar, .topbar[data-tone="dark"] { background: var(--clear); color: var(--on-dark); }
.stage .topbar .brand, .topbar[data-tone="dark"] .brand { color: var(--on-dark); }
.stage .topbar .tab, .topbar[data-tone="dark"] .tab { color: var(--on-dark-soft); }
.stage .topbar .tab:hover, .stage .topbar .tab[aria-current], .topbar[data-tone="dark"] .tab[aria-current] { color: var(--on-dark); }
.stage .topbar .tab[aria-current]::after, .topbar[data-tone="dark"] .tab[aria-current]::after { background: var(--accent-bright); }
.stage .topbar .lang, .stage .topbar .menu-toggle, .topbar[data-tone="dark"] .lang, .topbar[data-tone="dark"] .menu-toggle {
  border-color: var(--on-dark-line);
  background: var(--on-dark-fill);
  color: var(--on-dark);
}
.preview-header .topbar-inner { max-width: 1320px; }
.preview-menu { display: none; }
.preview-menu summary { list-style: none; }
.preview-menu summary::-webkit-details-marker { display: none; }

.site-footer { border-top: 1px solid var(--border); background: var(--bg); color: var(--text); padding-top: 64px; padding-bottom: 28px; }
.footer-grid { display: grid; grid-template-columns: 1.5fr 1fr 1.3fr 1fr; gap: 40px; }
.footer-brand p { margin-top: 18px; max-width: 28em; color: var(--text-muted); font-size: var(--size-sm); }
.footer-title { font-size: var(--size-body); font-weight: var(--weight-medium); margin-bottom: 14px; }
.footer-links { list-style: none; margin: 0; padding: 0; }
.footer-links a { display: inline-block; padding-block: 5px; color: var(--text-muted); font-size: var(--size-sm); }
.footer-links a:hover { color: var(--accent-dark); text-decoration: underline; text-underline-offset: 4px; }
.footer-bottom { margin-top: 48px; padding-top: 24px; border-top: 1px solid var(--border); display: flex; flex-wrap: wrap; justify-content: space-between; gap: 16px; color: var(--text-muted); font-size: var(--size-xs); }
.footer-legal { display: flex; flex-wrap: wrap; gap: 20px; }

.stage { position: relative; overflow: hidden; isolation: isolate; }
.stage::before {
  content: "";
  position: absolute;
  inset: 0 0 auto;
  height: var(--field-h);
  z-index: -1;
  background:
    radial-gradient(46% 30% at 8% 6%,var(--glow) 0%,var(--glow-clear) 72%),
    radial-gradient(40% 28% at 94% 14%,var(--glow) 0%,var(--glow-clear) 72%),
    linear-gradient(180deg,var(--hero-0) 0%,var(--hero-1) 20%,var(--hero-2) 46%,var(--hero-3) 68%,var(--hero-4) 84%,var(--bg) 100%);
}
.hero { text-align: center; padding: 28px 24px 0; }
.chips { display: flex; justify-content: center; flex-wrap: wrap; gap: 8px; list-style: none; padding: 0; margin: 0; }
.chip { display: inline-flex; align-items: center; gap: 8px; min-height: 26px; padding: 3px 12px; border-radius: var(--r-pill); border: 1px solid var(--on-dark-line); background: var(--on-dark-fill); color: var(--on-dark-soft); font-size: 12.5px; line-height: 1.3; }
.dot { width: 6px; height: 6px; border-radius: var(--r-round); background: var(--success); box-shadow: 0 0 0 3px var(--success-ring); }
.h1 { margin: 20px auto 0; max-width: 920px; font-size: clamp(30px,3.2vw,48px); color: var(--on-dark); }
.h1-line { display: block; }
.w { display: inline-block; white-space: nowrap; animation: rise .56s cubic-bezier(.2,.7,.2,1) both; }
.d1 { animation-delay: .12s; }
.d2 { animation-delay: .22s; }
.d3 { animation-delay: .32s; }
.d4 { animation-delay: .42s; }
.mark { position: relative; z-index: 0; }
.mark::after { content: ""; position: absolute; left: -.04em; right: -.04em; bottom: .05em; height: .3em; border-radius: var(--r-small); background: var(--hl); z-index: -1; transform-origin: left center; animation: sweep .44s .72s cubic-bezier(.3,.7,.2,1) both; }
@keyframes rise { from { opacity: 0; transform: translateY(.42em); } to { opacity: 1; transform: none; } }
@keyframes sweep { from { transform: scaleX(0); } to { transform: scaleX(1); } }
.lede { margin: 14px auto 0; max-width: 800px; font-size: 17px; line-height: 1.6; color: var(--on-dark-soft); }
.lede strong { color: var(--on-dark); font-weight: var(--weight-medium); }
.cta { display: flex; justify-content: center; flex-wrap: wrap; gap: 12px; margin-top: 26px; }
.hero .btn { height: 48px; padding-block: 0; }
.platforms { display: flex; justify-content: center; align-items: center; flex-wrap: wrap; gap: 26px; margin: 20px 0 0; padding: 0; list-style: none; }
.plat-label { font-size: 13px; color: var(--on-dark-soft); }
.plat a { display: inline-flex; align-items: center; gap: 7px; font-size: 13.5px; line-height: 22px; color: var(--on-dark-soft); transition: color var(--motion-fast); }
.plat a:hover { color: var(--on-dark); }
.plat svg { width: 15px; height: 15px; }
.hero :focus-visible, .stage .topbar .tab:focus-visible, .stage .topbar .lang:focus-visible { outline-color: var(--on-dark); }

.reveal { opacity: 1; transform: none; }
html.reveal-ready .reveal:not(.shown) { opacity: 0; transform: translateY(20px); }
.reveal { transition: opacity var(--motion-reveal) ease, transform var(--motion-reveal) ease; }
.reveal.shown { opacity: 1; transform: none; }
.decorated { position: relative; overflow-x: clip; isolation: isolate; }
.decoration { position: absolute; inset-inline: 0; pointer-events: none; }
.background-art { width: 100%; height: 100%; }
.statusbar { border-block: 1px solid var(--border); background: var(--bg-panel); color: var(--text-muted); }
.statusbar-inner { max-width: 1320px; margin-inline: auto; height: 42px; padding-inline: var(--gutter); display: flex; align-items: center; justify-content: center; gap: 28px; font-family: var(--font-mono); font-size: var(--size-xs); white-space: nowrap; overflow: hidden; }
.sb-item { display: inline-flex; align-items: center; gap: 8px; }
.sb-item b { font-weight: var(--weight-medium); color: var(--text); }
.sb-dot { width: 6px; height: 6px; border-radius: var(--r-round); background: var(--success); }

@media (max-width: 1280px) {
  .topbar-inner { gap: 24px; }
}
@media (max-width: 1100px) {
  .desktop-nav { display: none; }
  .header-tools { margin-left: auto; }
  .menu-toggle { display: inline-flex; }
  .preview-menu { display: block; }
  .preview-menu .menu-toggle { display: flex; }
  .preview-menu .mobile-drawer { top: var(--header-height); }
}
@media (min-width: 1101px) {
  .mobile-drawer, .menu-veil { display: none !important; }
}
@media (max-width: 900px) {
  .grid { grid-template-columns: repeat(2,minmax(0,1fr)); }
  .footer-grid { grid-template-columns: repeat(2,minmax(0,1fr)); }
  .section-heading { align-items: flex-start; }
}
@media (max-width: 768px) {
  h1 { font-size: clamp(24px,5vw,30px); }
}
@media (max-width: 640px) {
  :root { --gutter: 18px; --field-h: 640px; --card-h: 372px; --size-h2: 28px; }
  .topbar-inner { gap: 8px; }
  .brand { font-size: 14px; gap: 7px; }
  .brand-mark { width: 28px; height: 28px; }
  .header-tools { margin-left: auto; gap: 5px; }
  .lang { padding-inline: 10px; gap: 5px; }
  .lang-full { display: none; }
  .lang-short { display: inline; }
  .lang svg { display: none; }
  .hero { padding: 22px var(--gutter) 0; }
  .h1 { font-size: clamp(24px,7.4vw,30px); margin-top: 16px; }
  .lede { font-size: 15px; }
  .cta { margin-top: 22px; }
  .hero .btn { height: 46px; min-height: 46px; padding-inline: 22px; font-size: 15px; }
  .platforms { gap: 10px 18px; }
  .plat-label { display: none; }
  .chips { gap: 6px; }
  .chip { font-size: 11px; padding-inline: 9px; }
  .grid { grid-template-columns: minmax(0,1fr); }
  .section-heading { flex-direction: column; gap: 20px; }
  .panel, .surface-card { padding: 22px; }
  .footer-grid { grid-template-columns: minmax(0,1fr); gap: 32px; }
  .footer-bottom { flex-direction: column; }
  .statusbar-inner { justify-content: flex-start; }
  .tilt, [class*="tilt-"] { transform: none !important; }
  pre { padding: 18px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .w, .mark::after { animation: none; }
  .reveal, .tab, .btn, .plat a { transition: none; }
  html.reveal-ready .reveal:not(.shown) { opacity: 1; transform: none; }
}