*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:calc(var(--header-h) + 12px)}
body,h1,h2,h3,h4,h5,p,ul,ol,li,figure,blockquote,dl,dd{margin:0}
ul,ol{padding:0;list-style:none}
img,svg,video{max-width:100%;height:auto;display:block}
button{font:inherit;color:inherit;background:none;border:0;padding:0;cursor:pointer}
a{color:inherit;text-decoration:none}
[hidden]{display:none !important}

:root{
  --ink-900:#07131F;
  --ink-850:#081826;
  --ink-800:#0A1F30;
  --ink-700:#0D2233;
  --ink-600:#123047;
  --cyan:#31E6FF;
  --cyan-mist:#A9F6FF;
  --gold:#F6B84B;
  --amber:#FFD98A;
  --mint:#28D6A1;
  --paper:#F4F8FB;
  --slate:#6F8193;
  --coral:#FF6B5E;
  --line:rgba(169,246,255,.14);
  --line-strong:rgba(169,246,255,.32);
  --font-display:"HarmonyOS Sans SC","Noto Sans SC","Source Han Sans SC",system-ui,-apple-system,"PingFang SC","Microsoft YaHei",sans-serif;
  --font-body:system-ui,-apple-system,"PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  --font-mono:"JetBrains Mono","IBM Plex Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --header-h:100px;
  --wrap:1240px;
  --pad:clamp(16px,4vw,32px);
  --ease:cubic-bezier(.22,.61,.36,1);
}

body{
  background-color:var(--ink-900);
  background-image:
    linear-gradient(to right,rgba(169,246,255,.035) 1px,transparent 1px),
    linear-gradient(to bottom,rgba(169,246,255,.035) 1px,transparent 1px);
  background-size:72px 72px;
  color:var(--paper);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.75;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
h1,h2,h3,h4{font-family:var(--font-display);line-height:1.18;letter-spacing:-.01em;font-weight:600}
p,li{line-height:1.75}
strong{font-weight:700}
::selection{background:var(--cyan);color:var(--ink-900)}
:where(a,button,summary,input,[tabindex]):focus-visible{outline:2px solid var(--cyan);outline-offset:3px}

.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}

/* ---------- header ---------- */
.site-header{
  position:sticky;top:0;z-index:100;
  background:var(--ink-900);
  border-bottom:1px solid var(--line);
  transition:border-color .25s var(--ease);
}
.site-header.is-scrolled{border-bottom-color:var(--line-strong)}

.skip-link{
  position:fixed;top:0;left:8px;z-index:999;
  transform:translateY(-160%);
  background:var(--cyan);color:var(--ink-900);
  padding:10px 18px;font-family:var(--font-mono);font-size:12px;font-weight:700;letter-spacing:.12em;
  transition:transform .22s var(--ease);
}
.skip-link:focus-visible{transform:translateY(8px)}

.sync-bar{position:relative;background:var(--ink-850);border-bottom:1px solid var(--line)}
.sync-bar__inner{
  width:min(var(--wrap),100% - var(--pad)*2);
  margin-inline:auto;
  height:34px;
  display:flex;align-items:center;gap:clamp(10px,2vw,26px);
  font-family:var(--font-mono);
  font-size:11px;letter-spacing:.12em;
  color:var(--slate);
}
.sync-readout{display:flex;align-items:center;gap:8px}
.sync-readout__pulse{
  width:6px;height:6px;flex:0 0 6px;background:var(--mint);
  animation:pulse 2.4s var(--ease) infinite;
}
@keyframes pulse{
  0%{box-shadow:0 0 0 0 rgba(40,214,161,.5)}
  70%{box-shadow:0 0 0 7px rgba(40,214,161,0)}
  100%{box-shadow:0 0 0 0 rgba(40,214,161,0)}
}
.sync-readout__label{color:var(--slate);letter-spacing:.16em}
.sync-readout__time{color:var(--cyan);font-variant-numeric:tabular-nums;letter-spacing:.08em}
.sync-readout__meta{display:flex;align-items:center;gap:8px}
.sync-readout__meta--end{margin-left:auto}
.sync-readout__sep{color:var(--ink-600)}
.sync-readout__value{color:var(--paper);letter-spacing:.1em}
.sync-readout__meta--end .sync-readout__value{color:var(--gold)}

.scroll-meter{position:absolute;left:0;right:0;bottom:-1px;height:2px;background:rgba(169,246,255,.07);pointer-events:none}
.scroll-meter__fill{display:block;height:100%;width:0;background:linear-gradient(90deg,var(--cyan),var(--mint));transition:width .12s linear}

.cmd-bar{background:var(--ink-900)}
.cmd-bar__inner{
  width:min(var(--wrap),100% - var(--pad)*2);
  margin-inline:auto;
  height:64px;
  display:flex;align-items:center;gap:clamp(14px,3vw,40px);
}

.brand{display:inline-flex;align-items:center;gap:10px;flex:0 0 auto}
.brand__mark{
  font-family:var(--font-mono);font-weight:700;font-size:15px;letter-spacing:.02em;line-height:1;
  color:var(--ink-900);background:var(--cyan);
  padding:8px 9px 7px;
  clip-path:polygon(0 0,100% 0,100% 100%,9px 100%,0 calc(100% - 9px));
}
.brand__text{display:flex;flex-direction:column;line-height:1.1}
.brand__name{font-family:var(--font-display);font-weight:700;font-size:16px;letter-spacing:.08em;color:var(--paper)}
.brand__sub{font-family:var(--font-mono);font-size:9px;letter-spacing:.2em;color:var(--slate);margin-top:4px}

.nav{margin-left:auto}
.nav__list{display:flex;align-items:center;gap:clamp(2px,1.3vw,16px)}
.nav__item{position:relative}
.nav__link{
  display:inline-flex;align-items:baseline;gap:6px;
  padding:11px 5px;position:relative;
  color:var(--cyan-mist);font-size:13.5px;letter-spacing:.04em;
  transition:color .2s var(--ease);
}
.nav__idx{font-family:var(--font-mono);font-size:9.5px;letter-spacing:.06em;color:var(--gold);opacity:.75;transition:color .2s var(--ease),opacity .2s var(--ease)}
.nav__link::after{
  content:"";position:absolute;left:0;right:0;bottom:3px;height:2px;
  background:var(--cyan);transform:scaleX(0);transform-origin:left;
  transition:transform .28s var(--ease);
}
.nav__link:hover{color:var(--paper)}
.nav__link:hover::after{transform:scaleX(1)}
.nav__link[aria-current="page"]{color:var(--paper);font-weight:600}
.nav__link[aria-current="page"]::after{transform:scaleX(1)}
.nav__link[aria-current="page"] .nav__idx{color:var(--cyan);opacity:1}

.nav-toggle{
  display:none;align-items:center;gap:9px;margin-left:auto;
  padding:9px 12px;border:1px solid var(--line-strong);
  font-family:var(--font-mono);font-size:11px;letter-spacing:.16em;color:var(--cyan-mist);
  transition:border-color .2s var(--ease),color .2s var(--ease);
}
.nav-toggle:hover{border-color:var(--cyan);color:var(--cyan)}
.nav-toggle__bars{display:inline-flex;flex-direction:column;gap:4px;width:16px}
.nav-toggle__bars span{display:block;height:1.5px;background:currentColor;transition:transform .22s var(--ease)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:first-child{transform:translateY(2.75px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:last-child{transform:translateY(-2.75px) rotate(-45deg)}
.nav-toggle__label{line-height:1}

.version-dock{
  position:fixed;right:0;top:50%;transform:translateY(-50%);z-index:90;
  display:flex;flex-direction:column;align-items:center;gap:2px;
  padding:10px 5px;
  background:var(--ink-700);
  border:1px solid var(--line-strong);border-right:0;
}
.version-dock__caption{
  writing-mode:vertical-rl;
  font-family:var(--font-mono);font-size:9px;letter-spacing:.28em;color:var(--slate);
  margin-bottom:6px;
}
.version-dock__opt{
  writing-mode:vertical-rl;
  padding:11px 4px;font-size:11px;letter-spacing:.16em;line-height:1;
  color:var(--cyan-mist);border:1px solid transparent;
  transition:background .2s var(--ease),color .2s var(--ease),border-color .2s var(--ease);
}
.version-dock__opt:hover{color:var(--paper);border-color:var(--line-strong)}
.version-dock__opt.is-active{background:var(--cyan);color:var(--ink-900);font-weight:700;border-color:var(--cyan)}

/* ---------- footer ---------- */
.site-footer{
  position:relative;z-index:1;
  margin-top:clamp(40px,6vw,80px);
  background:var(--ink-850);
  border-top:1px solid var(--line);
}
.footer-band{display:grid;grid-template-columns:5fr 2fr 2fr 1fr;height:6px}
.footer-band__cell{display:block;height:100%}
.footer-band__cell--cyan{background:var(--cyan)}
.footer-band__cell--gold{background:var(--gold)}
.footer-band__cell--mint{background:var(--mint)}
.footer-band__cell--slate{background:var(--ink-600)}

.footer__inner{
  width:min(var(--wrap),100% - var(--pad)*2);
  margin-inline:auto;
  padding-block:clamp(34px,4.6vw,60px);
  display:grid;
  grid-template-columns:1.4fr 1fr 1fr 1.6fr;
  gap:clamp(22px,3vw,48px);
}
.footer__brand{
  font-family:var(--font-display);font-weight:700;font-size:clamp(22px,3vw,30px);
  letter-spacing:.02em;color:var(--paper);line-height:1.1;
}
.footer__brand-thin{font-weight:300;color:var(--cyan-mist);margin-left:4px}
.footer__note{margin-top:12px;max-width:24em;font-size:13px;line-height:1.75;color:var(--slate)}
.footer__nav-title{
  font-family:var(--font-mono);font-size:10px;letter-spacing:.26em;color:var(--gold);
  margin-bottom:14px;
}
.footer__list li + li{margin-top:9px}
.footer__link{
  position:relative;display:inline-block;
  font-size:13.5px;color:var(--cyan-mist);
  padding-left:0;transition:color .2s var(--ease),padding-left .2s var(--ease);
}
.footer__link::before{
  content:"";position:absolute;left:0;top:50%;width:0;height:1px;background:var(--cyan);
  transform:translateY(-50%);transition:width .2s var(--ease);
}
.footer__link:hover{color:var(--cyan);padding-left:14px}
.footer__link:hover::before{width:9px}
.footer__kv{display:flex;gap:10px;font-size:13px;line-height:1.7}
.footer__kv + .footer__kv{margin-top:8px}
.footer__k{
  flex:0 0 38px;padding-top:3px;
  font-family:var(--font-mono);font-size:10.5px;letter-spacing:.14em;color:var(--slate);
}
.footer__v{color:var(--cyan-mist);word-break:break-word}
.footer__v--mono{font-family:var(--font-mono);letter-spacing:.05em}
.footer__hint{
  margin-top:14px;padding-left:10px;border-left:2px solid var(--gold);
  font-size:11.5px;line-height:1.65;color:var(--slate);
}
.footer__base{
  width:min(var(--wrap),100% - var(--pad)*2);
  margin-inline:auto;
  border-top:1px solid var(--line);
  padding-block:18px;
  display:flex;flex-wrap:wrap;align-items:center;gap:10px 28px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.1em;color:var(--slate);
}
.footer__copy--end{margin-left:auto}
.footer__icp{color:var(--slate)}

/* ---------- shared layout ---------- */
.wrap{width:min(var(--wrap),100% - var(--pad)*2);margin-inline:auto}
.section{padding-block:clamp(44px,6.5vw,96px)}
.section + .section{border-top:1px solid var(--line)}
.section__head{max-width:64ch}
.sec-index{
  display:inline-flex;align-items:center;gap:10px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.28em;color:var(--gold);
}
.sec-index::before{content:"";width:28px;height:1px;background:currentColor}
.section__title{font-size:clamp(24px,3.4vw,36px);line-height:1.15;margin-top:14px;font-weight:700}
.section__lead{margin-top:12px;max-width:46ch;font-size:15px;line-height:1.8;color:var(--slate)}
.stack > * + *{margin-top:clamp(14px,2vw,24px)}
.rule-band{
  height:3px;
  background:linear-gradient(90deg,var(--cyan) 0 28%,var(--gold) 28% 52%,var(--mint) 52% 74%,var(--ink-600) 74% 100%);
}

.crumbs{
  display:flex;flex-wrap:wrap;align-items:center;gap:8px;
  padding-block:18px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.1em;color:var(--slate);
}
.crumbs a{color:var(--cyan-mist);transition:color .2s var(--ease)}
.crumbs a:hover{color:var(--cyan)}
.crumbs__sep{color:var(--ink-600)}
.crumbs [aria-current="page"]{color:var(--paper)}

.grid{display:grid;gap:clamp(14px,2vw,26px)}
.grid--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid--3{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid--sidebar{grid-template-columns:minmax(180px,240px) minmax(0,1fr)}

.panel{
  position:relative;
  background:var(--ink-700);
  border:1px solid var(--line);
  padding:clamp(16px,2.2vw,26px);
}
.panel--data{border-left:3px solid var(--mint)}
.panel--rule{border-left:3px solid var(--gold)}
.panel__title{font-family:var(--font-display);font-size:17px;font-weight:700;letter-spacing:.01em}
.panel__meta{font-family:var(--font-mono);font-size:10.5px;letter-spacing:.14em;color:var(--slate)}

.surface--data{background:linear-gradient(135deg,rgba(40,214,161,.13),rgba(7,19,31,0) 66%);border-left:2px solid var(--mint)}
.surface--rule{background:linear-gradient(135deg,rgba(246,184,75,.15),rgba(7,19,31,0) 66%);border-left:2px solid var(--gold)}

.btn{
  display:inline-flex;align-items:center;gap:8px;
  padding:12px 20px;
  font-size:13px;font-weight:600;letter-spacing:.08em;line-height:1.2;
  border:1px solid var(--line-strong);color:var(--paper);background:transparent;
  transition:background .2s var(--ease),color .2s var(--ease),border-color .2s var(--ease);
}
.btn--primary{background:var(--cyan);color:var(--ink-900);border-color:var(--cyan)}
.btn--primary:hover{background:var(--cyan-mist);border-color:var(--cyan-mist)}
.btn--ghost:hover{border-color:var(--cyan);color:var(--cyan)}
.btn--warm{background:var(--gold);color:var(--ink-900);border-color:var(--gold)}
.btn--warm:hover{background:var(--amber);border-color:var(--amber)}

.tag{
  display:inline-flex;align-items:center;gap:6px;
  padding:3px 9px;
  font-family:var(--font-mono);font-size:10.5px;letter-spacing:.14em;line-height:1.6;
  border:1px solid var(--line-strong);color:var(--cyan-mist);
  white-space:nowrap;
}
.tag--cyan{color:var(--cyan);border-color:rgba(49,230,255,.45);background:rgba(49,230,255,.08)}
.tag--gold{color:var(--gold);border-color:rgba(246,184,75,.45);background:rgba(246,184,75,.09)}
.tag--mint{color:var(--mint);border-color:rgba(40,214,161,.45);background:rgba(40,214,161,.08)}
.tag--mute{color:var(--slate);border-color:rgba(111,129,147,.35)}

.num{font-family:var(--font-mono);font-variant-numeric:tabular-nums;letter-spacing:-.01em}

.media{
  position:relative;overflow:hidden;
  background:linear-gradient(140deg,#0D2233 0%,#07131F 55%,#0A2E3C 100%);
  border:1px solid var(--line);
}
.media::after{
  content:"";position:absolute;inset:0;pointer-events:none;
  background-image:
    linear-gradient(to right,rgba(169,246,255,.07) 1px,transparent 1px),
    linear-gradient(to bottom,rgba(169,246,255,.07) 1px,transparent 1px);
  background-size:32px 32px;
}
.media > img{position:relative;z-index:1;width:100%;height:100%;object-fit:cover}
.media--16x9{aspect-ratio:16/9}
.media--4x3{aspect-ratio:4/3}
.media--1x1{aspect-ratio:1/1}
.media__placeholder{
  position:absolute;inset:0;z-index:1;
  display:flex;flex-direction:column;align-items:center;justify-content:center;gap:8px;
  padding:16px;text-align:center;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.2em;line-height:1.8;
  color:rgba(169,246,255,.55);
}

[data-reveal]{opacity:0;transform:translateY(14px);transition:opacity .6s var(--ease),transform .6s var(--ease)}
[data-reveal].is-visible{opacity:1;transform:none}

/* ---------- responsive ---------- */
@media (max-width:1180px){
  .version-dock{display:none}
}
@media (max-width:960px){
  .footer__inner{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer__intro{grid-column:1 / -1}
}
@media (max-width:900px){
  :root{--header-h:90px}
  .sync-bar__inner{height:28px;font-size:10px;gap:10px}
  .sync-readout__label{letter-spacing:.1em}
  .cmd-bar__inner{height:60px;gap:12px}
  .brand__name{font-size:15px}
  .brand__sub{font-size:8.5px;letter-spacing:.16em}
  .nav-toggle{display:inline-flex}
  .nav{
    position:fixed;top:var(--header-h);left:0;right:0;
    margin-left:0;
    background:var(--ink-800);
    border-bottom:1px solid var(--line-strong);
    max-height:0;overflow:hidden;visibility:hidden;opacity:0;
    transform:translateY(-6px);
    transition:opacity .22s var(--ease),transform .22s var(--ease),max-height .28s var(--ease),visibility .22s;
  }
  .nav[data-open]{
    max-height:calc(100dvh - var(--header-h));
    overflow-y:auto;
    visibility:visible;opacity:1;transform:translateY(0);
  }
  .nav__list{flex-direction:column;align-items:stretch;gap:0;padding:8px 0}
  .nav__item + .nav__item{border-top:1px solid var(--line)}
  .nav__link{display:flex;justify-content:space-between;align-items:baseline;padding:15px var(--pad);font-size:15px}
  .nav__link::after{display:none}
  .nav__link[aria-current="page"]{background:rgba(49,230,255,.08)}
  .grid--2,.grid--3,.grid--sidebar{grid-template-columns:minmax(0,1fr)}
  .footer__base{gap:8px 18px}
  .footer__copy--end{margin-left:0;width:100%}
}
@media (max-width:600px){
  .footer__inner{grid-template-columns:minmax(0,1fr);gap:26px}
  .footer__base{font-size:10px;letter-spacing:.06em}
  .section__lead{font-size:14px}
}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
  [data-reveal]{opacity:1;transform:none}
  .sync-readout__pulse{animation:none}
}