*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-padding-top:calc(var(--header-h) + 16px)}
body,h1,h2,h3,h4,p,ul,ol,li,figure,blockquote,dl,dd{margin:0;padding:0}
ul,ol{list-style:none}
img,svg,video{max-width:100%;height:auto}
button{font:inherit;color:inherit}
a{color:inherit;text-decoration:none}
:root{
  --ink-950:#050B14;--ink-900:#0A1626;--ink-800:#12233A;--line-600:#1F3A56;
  --paper:#F2F6FA;--mute:#8FA6BE;
  --cyan:#22E0D6;--acid:#A8F03C;--amber:#FF8A34;
  --cut:12px;--header-h:76px;--container:1200px;--wide:1320px;
  --font-sans:"Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",sans-serif;
  --font-cond:"Barlow Condensed","Oswald","Arial Narrow","Noto Sans SC",system-ui,sans-serif;
  --font-mono:"JetBrains Mono","SFMono-Regular",Consolas,"Liberation Mono","Courier New",monospace;
  --ease:cubic-bezier(.2,.7,.2,1);
}
body{
  font-family:var(--font-sans);font-size:17px;line-height:1.85;color:var(--paper);
  background-color:var(--ink-950);
  background-image:
    linear-gradient(to right,rgba(34,224,214,.045) 1px,transparent 1px),
    linear-gradient(to bottom,rgba(34,224,214,.045) 1px,transparent 1px);
  background-size:64px 64px;
  -webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;
  min-height:100vh;
}
:focus-visible{outline:2px solid var(--cyan);outline-offset:3px}
.visually-hidden{position:absolute;width:1px;height:1px;margin:-1px;padding:0;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.display-title{font-family:var(--font-cond);font-weight:700;font-size:clamp(44px,8vw,96px);line-height:.95;letter-spacing:-.02em}
/* ---------- skip link ---------- */
.skip-link{
  position:absolute;left:16px;top:8px;z-index:300;
  transform:translateY(-220%);
  background:var(--acid);color:#0A1626;font-size:14px;font-weight:700;letter-spacing:.02em;
  padding:10px 18px;transition:transform .18s var(--ease);
}
.skip-link:focus{transform:translateY(0);outline:2px solid var(--ink-950);outline-offset:2px}
/* ---------- header ---------- */
.site-header{
  position:sticky;top:0;z-index:100;
  background:linear-gradient(to bottom,rgba(5,11,20,.94) 0%,rgba(5,11,20,.64) 62%,rgba(5,11,20,0) 100%);
  border-bottom:1px solid transparent;
  transition:background .28s var(--ease),border-color .28s var(--ease);
}
.site-header[data-scrolled="true"]{background:rgba(10,22,38,.97);border-bottom-color:var(--line-600)}
.site-header[data-open="true"]{background:rgba(10,22,38,.99);border-bottom-color:var(--line-600)}
.read-progress{position:absolute;left:0;right:0;top:0;height:2px;background:rgba(31,58,86,.55);pointer-events:none;overflow:hidden}
.read-progress__fill{display:block;height:100%;width:100%;transform:scaleX(0);transform-origin:left center;background:linear-gradient(90deg,var(--cyan) 0%,var(--cyan) 55%,var(--amber) 100%);transition:transform .1s linear}
.site-header__inner{
  display:flex;align-items:center;gap:16px;
  max-width:var(--wide);margin:0 auto;padding:0 24px;height:var(--header-h);
}
/* brand */
.brand{display:inline-flex;align-items:center;gap:12px;flex:0 0 auto}
.brand__mark{
  display:inline-block;font-family:var(--font-mono);font-weight:700;font-size:19px;line-height:1;
  letter-spacing:.06em;color:#03161A;background:var(--cyan);padding:9px 11px 8px;
  clip-path:polygon(0 0,100% 0,100% 70%,calc(100% - 9px) 100%,0 100%);
  transition:background .2s var(--ease);
}
.brand:hover .brand__mark{background:#5CF0E8}
.brand__text{display:flex;flex-direction:column;gap:2px}
.brand__line{font-size:15px;font-weight:700;letter-spacing:.06em;color:var(--paper);line-height:1.2}
.brand__tag{font-family:var(--font-mono);font-size:10px;letter-spacing:.08em;color:var(--mute);line-height:1.3}
/* nav */
.site-nav{margin-left:auto;display:flex;align-items:center}
.site-nav__list{display:flex;align-items:center;gap:2px}
.site-nav__item{position:relative}
.site-nav__link{
  position:relative;display:flex;align-items:baseline;gap:6px;
  padding:10px 13px;font-size:15px;font-weight:500;letter-spacing:.01em;color:var(--paper);
  transition:color .2s var(--ease);
}
.site-nav__index{font-family:var(--font-mono);font-size:10px;letter-spacing:.06em;color:var(--line-600);transition:color .2s var(--ease)}
.site-nav__link::after{
  content:"";position:absolute;left:13px;right:13px;bottom:3px;height:2px;
  background:var(--cyan);transform:scaleX(0);transform-origin:left center;
  transition:transform .22s var(--ease);
}
.site-nav__link:hover,.site-nav__link:focus-visible{color:var(--cyan)}
.site-nav__link:hover .site-nav__index,.site-nav__link:focus-visible .site-nav__index{color:var(--cyan)}
.site-nav__link:hover::after,.site-nav__link:focus-visible::after{transform:scaleX(1)}
.site-nav__link[aria-current="page"]{color:var(--cyan)}
.site-nav__link[aria-current="page"] .site-nav__index{color:var(--cyan)}
.site-nav__link[aria-current="page"]::after{transform:scaleX(1)}
.site-nav__foot{display:none}
.site-nav__note{font-family:var(--font-mono);font-size:11px;line-height:1.7;letter-spacing:.04em;color:var(--mute)}
.header-actions{display:flex;align-items:center;gap:12px;margin-left:22px;flex:0 0 auto}
/* buttons */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  font-family:var(--font-sans);font-size:14px;font-weight:700;letter-spacing:.02em;line-height:1;
  padding:13px 20px;border:1px solid transparent;cursor:pointer;white-space:nowrap;
  clip-path:polygon(0 0,calc(100% - 10px) 0,100% 10px,100% 100%,10px 100%,0 calc(100% - 10px));
  transition:background .2s var(--ease),color .2s var(--ease),border-color .2s var(--ease);
}
.btn:focus-visible{outline:2px solid var(--acid);outline-offset:-4px}
.btn--primary{background:var(--cyan);color:#03161A}
.btn--primary:hover{background:#5CF0E8}
.btn--ghost{background:transparent;color:var(--paper);border-color:var(--line-600)}
.btn--ghost:hover{border-color:var(--cyan);color:var(--cyan)}
/* mobile toggle */
.nav-toggle{
  display:none;align-items:center;gap:9px;
  background:transparent;border:1px solid var(--line-600);color:var(--paper);
  padding:10px 12px;cursor:pointer;
  clip-path:polygon(0 0,calc(100% - 8px) 0,100% 8px,100% 100%,8px 100%,0 calc(100% - 8px));
  transition:border-color .2s var(--ease),color .2s var(--ease);
}
.nav-toggle:hover{border-color:var(--cyan);color:var(--cyan)}
.nav-toggle__label{font-family:var(--font-mono);font-size:11px;letter-spacing:.14em}
.nav-toggle__bars{display:inline-flex;flex-direction:column;gap:3px;width:16px}
.nav-toggle__bars i{display:block;height:2px;background:currentColor;transition:width .2s var(--ease)}
.nav-toggle__bars i:nth-child(1){width:100%}
.nav-toggle__bars i:nth-child(2){width:70%}
.nav-toggle__bars i:nth-child(3){width:44%}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(2){width:100%}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(3){width:100%}
/* to top */
.to-top{
  position:fixed;right:20px;bottom:20px;z-index:95;
  width:44px;height:44px;display:inline-flex;align-items:center;justify-content:center;
  background:var(--ink-800);color:var(--cyan);border:1px solid var(--line-600);
  font-family:var(--font-mono);font-size:16px;line-height:1;cursor:pointer;
  clip-path:polygon(0 0,calc(100% - 10px) 0,100% 10px,100% 100%,10px 100%,0 calc(100% - 10px));
  transition:background .2s var(--ease),color .2s var(--ease),border-color .2s var(--ease);
}
.to-top:hover{background:var(--cyan);color:#03161A;border-color:var(--cyan)}
.to-top[hidden]{display:none}
/* ---------- layout helpers ---------- */
.container{width:100%;max-width:var(--container);margin:0 auto;padding:0 24px}
.section{padding:96px 0}
.section--tight{padding:64px 0}
.section-head{display:flex;flex-direction:column;gap:12px;margin-bottom:36px;max-width:720px}
.kicker{display:inline-flex;align-items:center;gap:9px;font-family:var(--font-mono);font-size:12px;letter-spacing:.18em;text-transform:uppercase;color:var(--cyan)}
.kicker::before{content:"";display:block;width:20px;height:2px;background:var(--cyan)}
.section-title{font-size:clamp(28px,3.6vw,40px);font-weight:900;letter-spacing:-.02em;line-height:1.06}
.section-desc{max-width:560px;color:var(--mute);font-size:15px;line-height:1.78}
.hero-bleed{margin-top:calc(var(--header-h) * -1);padding-top:calc(var(--header-h) + 64px)}
.slash-rule{height:10px;background:repeating-linear-gradient(115deg,var(--line-600) 0 2px,transparent 2px 12px);opacity:.75}
.grid{display:grid;gap:24px}
.grid--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid--3{grid-template-columns:repeat(3,minmax(0,1fr))}
/* ---------- panels / tags / media ---------- */
.panel{
  position:relative;background:var(--ink-800);border:1px solid var(--line-600);padding:26px;
  clip-path:polygon(0 0,calc(100% - var(--cut)) 0,100% var(--cut),100% 100%,var(--cut) 100%,0 calc(100% - var(--cut)));
  transition:border-color .2s var(--ease),transform .2s var(--ease);
}
.panel--flat{background:var(--ink-900)}
.panel:hover{border-color:rgba(34,224,214,.55);transform:translateY(-2px)}
.panel__index{display:block;font-family:var(--font-mono);font-size:12px;letter-spacing:.16em;color:var(--cyan);margin-bottom:12px}
.panel__title{font-size:21px;font-weight:700;letter-spacing:-.01em;line-height:1.3;margin-bottom:10px}
.tag{
  display:inline-flex;align-items:center;gap:6px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.08em;line-height:1;
  padding:6px 10px;border:1px solid var(--line-600);color:var(--mute);background:rgba(18,35,58,.65);
}
.tag--acid{background:var(--acid);border-color:var(--acid);color:#0A1626}
.tag--cyan{color:var(--cyan);border-color:rgba(34,224,214,.5);background:rgba(34,224,214,.08)}
.tag--amber{color:var(--amber);border-color:rgba(255,138,52,.55);background:rgba(255,138,52,.08)}
.media-frame{
  position:relative;display:block;overflow:hidden;aspect-ratio:16/9;
  background:var(--ink-800);border:1px solid var(--line-600);
  clip-path:polygon(0 0,calc(100% - var(--cut)) 0,100% var(--cut),100% 100%,var(--cut) 100%,0 calc(100% - var(--cut)));
}
.media-frame img,.media-frame picture,.media-frame video{display:block;width:100%;height:100%;object-fit:cover}
.media-frame::after{
  content:"";position:absolute;inset:0;pointer-events:none;
  background-image:linear-gradient(115deg,transparent 0 61%,rgba(34,224,214,.18) 61% 61.7%,transparent 61.7%);
}
.media-frame--wide{aspect-ratio:21/9}
.media-frame--tall{aspect-ratio:3/4}
.media-frame--square{aspect-ratio:1/1}
/* ---------- prose & breadcrumb ---------- */
.prose{max-width:640px;font-size:17px;line-height:1.85;color:var(--paper);letter-spacing:.01em}
.prose p+p{margin-top:1.1em}
.prose h2{font-size:clamp(22px,2.4vw,28px);font-weight:900;letter-spacing:-.01em;line-height:1.24;margin:2em 0 .7em}
.prose h3{font-size:21px;font-weight:700;line-height:1.35;margin:1.6em 0 .55em}
.prose a{color:var(--cyan);border-bottom:1px solid rgba(34,224,214,.4);transition:border-color .2s var(--ease)}
.prose a:hover{border-bottom-color:var(--cyan)}
.prose ul{margin:1em 0}
.prose ul li{position:relative;padding-left:20px;margin:.5em 0}
.prose ul li::before{content:"";position:absolute;left:0;top:.78em;width:10px;height:2px;background:var(--cyan)}
.prose blockquote{border-left:2px solid var(--amber);padding-left:16px;color:var(--mute)}
.prose code{font-family:var(--font-mono);font-size:.92em;color:var(--acid)}
.breadcrumb{font-family:var(--font-mono);font-size:12px;letter-spacing:.06em;color:var(--mute)}
.breadcrumb__list{display:flex;flex-wrap:wrap;align-items:center;gap:10px}
.breadcrumb__item{display:inline-flex;align-items:center}
.breadcrumb__item+.breadcrumb__item::before{content:"／";color:var(--line-600);margin-right:10px}
.breadcrumb__item a{color:var(--mute);transition:color .2s var(--ease)}
.breadcrumb__item a:hover{color:var(--cyan)}
.breadcrumb__item[aria-current="page"]{color:var(--paper)}
/* ---------- reveal ---------- */
[data-reveal]{transition:opacity .24s var(--ease),transform .24s var(--ease)}
.js-reveal [data-reveal]{opacity:0;transform:translateY(12px)}
.js-reveal [data-reveal].is-visible{opacity:1;transform:none}
/* ---------- footer ---------- */
.site-footer{position:relative;margin-top:120px;background:var(--ink-900);border-top:1px solid var(--line-600)}
.footer__stripe{height:6px;background:linear-gradient(90deg,var(--cyan) 0 22%,var(--amber) 22% 29%,var(--acid) 29% 32%,var(--ink-800) 32% 100%)}
.footer__inner{max-width:var(--container);margin:0 auto;padding:0 24px}
.footer__top{display:grid;grid-template-columns:1.6fr repeat(4,minmax(0,1fr));gap:44px 32px;padding:64px 0 48px}
.footer__brand{display:flex;flex-direction:column;align-items:flex-start;gap:18px}
.brand--footer .brand__mark{font-size:17px;padding:8px 10px 7px}
.footer__intro{font-size:15px;line-height:1.8;color:var(--mute);max-width:34em}
.footer__back{margin-top:2px}
.footer__col{min-width:0}
.footer__title{
  font-family:var(--font-mono);font-size:11px;font-weight:500;letter-spacing:.2em;text-transform:uppercase;
  color:var(--mute);padding-bottom:10px;border-bottom:1px solid var(--line-600);line-height:1.4;
}
.footer__list{display:flex;flex-direction:column;gap:11px;margin-top:16px}
.footer__list a{
  position:relative;display:inline-block;font-size:15px;color:var(--mute);
  transition:color .2s var(--ease),padding-left .2s var(--ease);
}
.footer__list a::before{
  content:"";position:absolute;left:0;top:.74em;width:0;height:2px;background:var(--cyan);
  transition:width .2s var(--ease);
}
.footer__list a:hover,.footer__list a:focus-visible{color:var(--paper);padding-left:15px}
.footer__list a:hover::before,.footer__list a:focus-visible::before{width:9px}
.footer__meta{
  display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px 32px;
  padding:28px 0;border-top:1px solid var(--line-600);
}
.footer__meta-item{display:flex;flex-direction:column;gap:5px}
.footer__label{font-family:var(--font-mono);font-size:11px;letter-spacing:.14em;text-transform:uppercase;color:var(--mute)}
.footer__value{font-family:var(--font-mono);font-size:14px;line-height:1.6;color:var(--paper);word-break:break-word}
.footer__meta-item--note{grid-column:1/-1;font-size:13px;line-height:1.75;color:var(--mute);padding-top:4px}
.footer__bottom{
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:10px 24px;
  padding:20px 0 34px;border-top:1px solid var(--line-600);
}
.footer__copy,.footer__icp{font-family:var(--font-mono);font-size:12px;letter-spacing:.03em;color:var(--mute);line-height:1.7}
.footer__icp{color:var(--line-600)}
/* ---------- responsive ---------- */
@media (max-width:1100px){
  .footer__top{grid-template-columns:1.4fr repeat(2,minmax(0,1fr));gap:36px 28px}
  .footer__brand{grid-column:1/-1}
}
@media (max-width:920px){
  :root{--header-h:64px}
  .site-header__inner{padding:0 16px;gap:10px}
  .brand__tag{display:none}
  .nav-toggle{display:inline-flex}
  .header-actions{margin-left:auto}
  .header-actions__cta{display:none}
  .site-nav{
    position:absolute;left:0;right:0;top:100%;
    display:none;flex-direction:column;align-items:stretch;margin-left:0;
    background:var(--ink-900);border-top:1px solid var(--line-600);border-bottom:1px solid var(--line-600);
    padding:12px 16px 24px;max-height:calc(100vh - var(--header-h));overflow-y:auto;
  }
  .site-header[data-open="true"] .site-nav{display:flex}
  .site-nav__list{flex-direction:column;align-items:stretch;gap:0}
  .site-nav__link{
    padding:15px 2px;font-size:17px;font-weight:700;
    border-bottom:1px solid rgba(31,58,86,.65);
  }
  .site-nav__link::after{display:none}
  .site-nav__link[aria-current="page"]{padding-left:14px}
  .site-nav__link[aria-current="page"]::before{
    content:"";position:absolute;left:0;top:50%;width:8px;height:2px;background:var(--cyan);transform:translateY(-50%);
  }
  .site-nav__index{font-size:11px;color:var(--mute)}
  .site-nav__foot{display:flex;flex-direction:column;gap:12px;margin-top:18px}
  .container{padding:0 16px}
  .section{padding:64px 0}
  .grid--3{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer__meta{grid-template-columns:repeat(2,minmax(0,1fr))}
  .site-footer{margin-top:80px}
}
@media (max-width:640px){
  body{font-size:16px;background-size:48px 48px}
  .brand__mark{font-size:16px;padding:8px 9px 7px}
  .brand__line{font-size:14px}
  .grid--2,.grid--3{grid-template-columns:1fr}
  .panel{padding:20px}
  .footer__top{grid-template-columns:repeat(2,minmax(0,1fr));padding:48px 0 36px}
  .footer__meta{grid-template-columns:1fr}
  .footer__bottom{flex-direction:column;align-items:flex-start}
  .to-top{right:14px;bottom:14px;width:40px;height:40px}
}
@media (max-width:400px){
  .footer__top{grid-template-columns:1fr}
}
@media (prefers-reduced-motion: reduce){
  *,*::before,*::after{
    animation-duration:.001ms !important;animation-iteration-count:1 !important;
    transition-duration:.001ms !important;scroll-behavior:auto !important;
  }
  .js-reveal [data-reveal]{opacity:1 !important;transform:none !important}
  .panel:hover{transform:none}
}