/* ===== 01 reset & tokens ===== */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body,h1,h2,h3,h4,p,ul,ol,li,figure,blockquote,dl,dd{margin:0}
ul,ol{padding:0;list-style:none}
img,svg{max-width:100%;display:block}
:root{
  --ink-900:#071528;
  --ink-800:#0B1F3A;
  --ink-700:#12325A;
  --ink-600:#1B4472;
  --cyan:#00E5FF;
  --cyan-soft:#7DF3FF;
  --orange:#FF6B35;
  --orange-soft:#FFB199;
  --silver:#AEB9C9;
  --paper:#F4F7FB;
  --violet:#7B61FF;
  --line:rgba(174,185,201,.22);
  --line-soft:rgba(174,185,201,.13);
  --shell:1320px;
  --gutter:clamp(16px,4vw,48px);
  --radius-lg:26px;
  --radius-md:14px;
  --radius-sm:6px;
  --font-display:"Haettenschweiler","Arial Narrow",Impact,"Franklin Gothic Heavy","Noto Sans SC","PingFang SC",sans-serif;
  --font-body:"Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,sans-serif;
  --font-mono:"IBM Plex Mono","Roboto Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --ease:cubic-bezier(.22,.61,.36,1);
}
body{
  background:var(--ink-800);
  color:var(--paper);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.72;
  letter-spacing:.01em;
  overflow-x:hidden;
}
body.nav-open{overflow:hidden}
h1,h2,h3,h4{line-height:1.16;font-weight:800;letter-spacing:.005em}
p{max-width:72ch}
a{color:inherit}
:where(a,button,[tabindex]):focus-visible{outline:2px solid var(--cyan);outline-offset:3px;border-radius:2px}
::selection{background:var(--cyan);color:var(--ink-900)}
.shell{width:min(100% - var(--gutter) * 2, var(--shell));margin-inline:auto}

/* ===== 02 skip link ===== */
.skip-link{
  position:fixed;top:10px;left:10px;z-index:300;
  padding:11px 18px;
  background:var(--cyan);color:#04131f;
  font:600 14px/1 var(--font-body);text-decoration:none;
  border-radius:2px;
  transform:translateY(-180%);
  transition:transform .18s var(--ease);
}
.skip-link:focus,.skip-link:focus-visible{transform:translateY(0)}

/* ===== 03 header frame ===== */
.arena-header{
  position:sticky;top:0;z-index:90;
  background:linear-gradient(180deg,var(--ink-900) 0%,var(--ink-800) 100%);
  border-bottom:1px solid rgba(0,229,255,.24);
  box-shadow:0 18px 40px -32px rgba(0,0,0,.9);
}
.arena-header::before{
  content:"";position:absolute;inset:0;pointer-events:none;
  background:repeating-linear-gradient(115deg,rgba(0,229,255,.045) 0 1px,transparent 1px 15px);
}
.arena-header__strip{
  position:relative;
  background:rgba(7,21,40,.86);
  border-bottom:1px solid var(--line-soft);
}
.strip{
  display:flex;align-items:center;justify-content:space-between;gap:18px;
  min-height:38px;
  font:500 12px/1.5 var(--font-mono);
  letter-spacing:.07em;color:var(--silver);
}
.strip__note{display:flex;align-items:center;gap:10px;margin:0;max-width:none;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.strip__pulse{
  flex:0 0 auto;width:7px;height:7px;border-radius:50%;
  background:var(--cyan);box-shadow:0 0 0 0 rgba(0,229,255,.55);
  animation:pulse 2.6s var(--ease) infinite;
}
@keyframes pulse{
  0%,100%{box-shadow:0 0 0 0 rgba(0,229,255,.45)}
  55%{box-shadow:0 0 0 7px rgba(0,229,255,0)}
}
.strip__utility{display:flex;align-items:center;gap:20px;flex:0 0 auto}
.strip__link{
  color:var(--silver);text-decoration:none;
  padding-bottom:2px;border-bottom:1px solid transparent;
  transition:color .16s var(--ease),border-color .16s var(--ease);
}
.strip__link:hover,.strip__link:focus-visible{color:var(--cyan);border-color:var(--cyan)}

.arena-header__bar{position:relative;z-index:95}
.bar{
  display:flex;align-items:center;gap:clamp(14px,2.4vw,40px);
  min-height:78px;padding-block:10px;
}
.brand{
  display:inline-flex;align-items:center;gap:12px;
  text-decoration:none;color:var(--paper);flex:0 0 auto;
}
.brand__glyph{
  display:grid;place-items:center;
  width:46px;height:46px;
  font:400 20px/1 var(--font-display);
  letter-spacing:.03em;color:#04131f;
  background:linear-gradient(135deg,var(--cyan) 0%,var(--cyan-soft) 46%,var(--violet) 100%);
  clip-path:polygon(14% 0,100% 0,86% 100%,0 100%);
  transition:background .2s var(--ease);
}
.brand:hover .brand__glyph{background:linear-gradient(135deg,var(--cyan-soft) 0%,var(--orange) 100%)}
.brand__text{display:flex;flex-direction:column;gap:4px;line-height:1}
.brand__name{font-family:var(--font-display);font-weight:800;font-size:26px;letter-spacing:.03em;color:var(--paper)}
.brand__sub{font:500 10px/1 var(--font-mono);letter-spacing:.24em;color:var(--cyan)}
.brand--footer .brand__name{font-size:31px}
.brand--footer .brand__glyph{width:52px;height:52px;font-size:23px}

.nav{margin-inline-start:auto}
.nav__list{display:flex;align-items:center;gap:clamp(2px,1.2vw,16px)}
.nav__link{
  position:relative;display:inline-flex;align-items:baseline;gap:7px;
  padding:11px 9px 13px;
  color:var(--paper);text-decoration:none;
  font-size:15px;font-weight:500;letter-spacing:.015em;
  transition:color .16s var(--ease);
}
.nav__idx{font:500 10px/1 var(--font-mono);letter-spacing:.11em;color:var(--silver);transition:color .16s var(--ease)}
.nav__link::after{
  content:"";position:absolute;left:9px;right:9px;bottom:5px;height:2px;
  background:var(--cyan);transform:scaleX(0);transform-origin:left;
  transition:transform .18s var(--ease);
}
.nav__link:hover,.nav__link:focus-visible{color:var(--cyan-soft)}
.nav__link:hover::after,.nav__link:focus-visible::after{transform:scaleX(1)}
.nav__link[aria-current="page"]{color:var(--cyan)}
.nav__link[aria-current="page"]::after{transform:scaleX(1);background:linear-gradient(90deg,var(--cyan),var(--orange))}
.nav__link[aria-current="page"] .nav__idx{color:var(--orange)}
.nav__cta{display:none}

.bar__actions{display:flex;align-items:center;gap:12px;flex:0 0 auto}
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  min-height:44px;padding:0 24px;
  border:1px solid transparent;border-radius:2px;
  font-family:var(--font-body);font-size:14px;font-weight:700;letter-spacing:.05em;
  text-decoration:none;cursor:pointer;
  transition:transform .16s var(--ease),background-color .16s var(--ease),color .16s var(--ease),border-color .16s var(--ease);
}
.btn:hover{transform:translateY(-1px)}
.btn--accent{
  background:var(--orange);color:#150800;
  clip-path:polygon(11px 0,100% 0,calc(100% - 11px) 100%,0 100%);
}
.btn--accent:hover{background:var(--orange-soft)}
.btn--cyan{
  background:var(--cyan);color:#04131f;
  clip-path:polygon(11px 0,100% 0,calc(100% - 11px) 100%,0 100%);
}
.btn--cyan:hover{background:var(--cyan-soft)}
.btn--ghost{background:transparent;color:var(--cyan);border-color:rgba(0,229,255,.5)}
.btn--ghost:hover{background:rgba(0,229,255,.12);border-color:var(--cyan)}

.nav-toggle{
  display:none;align-items:center;gap:9px;
  min-height:44px;padding:0 14px;
  background:rgba(18,50,90,.7);color:var(--paper);
  border:1px solid rgba(0,229,255,.36);border-radius:2px;
  font:600 13px/1 var(--font-body);letter-spacing:.06em;cursor:pointer;
}
.nav-toggle__bars{display:grid;gap:4px;width:18px}
.nav-toggle__bars i{display:block;height:2px;background:var(--cyan);transition:transform .18s var(--ease),opacity .18s var(--ease)}
.arena-header[data-open="true"] .nav-toggle__bars i:nth-child(1){transform:translateY(6px) rotate(45deg)}
.arena-header[data-open="true"] .nav-toggle__bars i:nth-child(2){opacity:0}
.arena-header[data-open="true"] .nav-toggle__bars i:nth-child(3){transform:translateY(-6px) rotate(-45deg)}

.scroll-progress{
  position:absolute;left:0;right:0;bottom:-1px;height:2px;
  background:rgba(0,229,255,.14);pointer-events:none;
}
.scroll-progress__fill{
  display:block;height:100%;width:100%;
  background:linear-gradient(90deg,var(--cyan),var(--orange));
  transform:scaleX(0);transform-origin:left;
  transition:transform .1s linear;
}

/* ===== 04 footer ===== */
.arena-footer{
  position:relative;
  margin-top:clamp(56px,8vw,110px);
  background:linear-gradient(180deg,var(--ink-900) 0%,#050f1d 100%);
  color:var(--paper);
  border-top:1px solid rgba(0,229,255,.22);
  overflow:hidden;
}
.footer__slab{
  position:absolute;inset:0 0 auto 0;height:200px;pointer-events:none;
  background:
    linear-gradient(180deg,rgba(18,50,90,.85),transparent 78%),
    repeating-linear-gradient(115deg,rgba(0,229,255,.09) 0 1px,transparent 1px 20px);
  clip-path:polygon(0 0,100% 0,100% 58%,0 100%);
}
.footer__grid{
  position:relative;
  display:grid;grid-template-columns:minmax(0,1.05fr) minmax(0,1.9fr);
  gap:clamp(30px,5vw,72px);
  padding-block:clamp(44px,6vw,80px) clamp(26px,4vw,44px);
}
.footer__brand{display:flex;flex-direction:column;gap:20px}
.footer__line{
  max-width:32ch;color:var(--silver);font-size:15px;line-height:1.75;
  border-left:2px solid var(--orange);padding-left:14px;
}
.footer__contact{display:grid;gap:10px}
.footer__contact li{display:flex;flex-wrap:wrap;align-items:baseline;gap:8px 10px}
.footer__key{
  font:500 11px/1.6 var(--font-mono);letter-spacing:.14em;color:var(--cyan);
  min-width:66px;
}
.footer__val{color:var(--paper);font-size:14px;word-break:break-all}
.copy{
  padding:4px 9px;
  background:rgba(0,229,255,.1);color:var(--cyan);
  border:1px solid rgba(0,229,255,.4);border-radius:999px;
  font:600 11px/1.4 var(--font-body);letter-spacing:.06em;cursor:pointer;
  transition:background-color .16s var(--ease),color .16s var(--ease);
}
.copy:hover{background:var(--cyan);color:#04131f}
.copy.is-copied{background:var(--orange);border-color:var(--orange);color:#150800}
.footer__cols{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:clamp(20px,3vw,40px)}
.footer__col-title{
  font:500 12px/1 var(--font-mono);letter-spacing:.18em;color:var(--cyan);
  text-transform:uppercase;margin-bottom:16px;
}
.footer__col-title::before{content:"/ ";color:var(--orange)}
.footer__list{display:grid;gap:2px}
.footer__link{
  display:inline-block;padding:6px 0;
  color:var(--silver);text-decoration:none;font-size:14.5px;
  border-bottom:1px solid transparent;
  transition:color .16s var(--ease),border-color .16s var(--ease);
}
.footer__link:hover,.footer__link:focus-visible{color:var(--cyan-soft);border-color:rgba(0,229,255,.6)}
.footer__legal{
  position:relative;
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:10px 24px;
  padding-block:18px 22px;
  border-top:1px solid var(--line-soft);
  font:500 12px/1.7 var(--font-mono);letter-spacing:.06em;color:var(--silver);
}
.footer__legal-note{max-width:none}
.footer__region{color:var(--cyan);letter-spacing:.18em}

/* ===== 05 shared layout helpers ===== */
.page-body{padding-block:clamp(28px,5vw,64px)}
.section{padding-block:clamp(28px,4vw,56px)}
.section__head{
  display:grid;grid-template-columns:auto minmax(0,1fr);gap:clamp(14px,2.4vw,32px);
  align-items:start;margin-bottom:clamp(18px,3vw,32px);
}
.section__index{
  font-family:var(--font-display);font-weight:800;
  font-size:clamp(2.4rem,5vw,4.8rem);line-height:.86;letter-spacing:.01em;
  color:rgba(0,229,255,.34);
}
.section__title{font-size:clamp(1.35rem,2.4vw,2.1rem)}
.section__note{color:var(--silver);font-size:15px;margin-top:10px;max-width:62ch}
.lede{font-size:clamp(1rem,1.5vw,1.18rem);line-height:1.78;color:rgba(244,247,251,.88);max-width:64ch}
.stack{display:grid;gap:clamp(14px,2vw,24px)}
.divider{height:1px;background:var(--line);border:0;margin-block:clamp(20px,3vw,36px)}
.grid{display:grid;gap:clamp(16px,2.4vw,32px)}
.grid--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid--3{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid--split{grid-template-columns:minmax(0,1.7fr) minmax(0,1fr)}
.num{font-family:var(--font-mono);letter-spacing:.04em;font-variant-numeric:tabular-nums}

/* ===== 06 cards, tags, lists ===== */
.card{
  position:relative;
  padding:clamp(18px,2.4vw,28px);
  background:linear-gradient(160deg,rgba(18,50,90,.92),rgba(7,21,40,.92));
  border:1px solid var(--line);
  border-left:3px solid var(--cyan);
  border-radius:2px var(--radius-md) var(--radius-md) 2px;
  transition:transform .18s var(--ease),border-color .18s var(--ease);
}
.card:hover{transform:translateY(-3px);border-left-color:var(--orange)}
.card__index{
  display:block;font:500 11px/1 var(--font-mono);letter-spacing:.18em;
  color:var(--cyan);margin-bottom:12px;
}
.card__title{font-size:clamp(1.05rem,1.5vw,1.25rem);margin-bottom:8px}
.card__meta{font-size:13px;color:var(--silver)}
.card--light{background:var(--paper);color:#16283f;border-color:rgba(11,31,58,.16);border-left-color:var(--violet)}
.card--light .card__index{color:var(--violet)}
.card--light .card__meta{color:#4c5f78}
.tag{
  display:inline-flex;align-items:center;gap:6px;
  padding:4px 11px;border-radius:999px;
  font:600 11.5px/1.6 var(--font-mono);letter-spacing:.08em;
  border:1px solid currentColor;
}
.tag--cyan{color:var(--cyan);background:rgba(0,229,255,.1)}
.tag--orange{color:var(--orange);background:rgba(255,107,53,.12)}
.tag--violet{color:var(--violet);background:rgba(123,97,255,.14)}

/* ===== 07 tables ===== */
.data-table{width:100%;border-collapse:collapse;font-size:14.5px}
.data-table caption{
  text-align:left;font:500 12px/1.6 var(--font-mono);letter-spacing:.12em;
  color:var(--cyan);padding-bottom:12px;
}
.data-table th,.data-table td{
  padding:13px 14px;text-align:left;
  border-bottom:1px solid var(--line-soft);
  vertical-align:top;
}
.data-table th{
  font:600 12px/1.5 var(--font-mono);letter-spacing:.1em;
  color:var(--silver);background:rgba(18,50,90,.6);
}
.data-table td{color:rgba(244,247,251,.9)}
.data-row:hover td{background:rgba(0,229,255,.06)}
.data-cell--num{font-family:var(--font-mono);color:var(--cyan)}

/* ===== 08 filter bar ===== */
.filter-bar{display:flex;flex-wrap:wrap;align-items:center;gap:8px}
.filter-btn{
  padding:9px 16px;border-radius:999px;
  background:transparent;color:var(--silver);
  border:1px solid var(--line);
  font:600 13px/1.2 var(--font-body);letter-spacing:.04em;cursor:pointer;
  transition:background-color .16s var(--ease),color .16s var(--ease),border-color .16s var(--ease);
}
.filter-btn:hover{border-color:var(--cyan);color:var(--cyan-soft)}
.filter-btn[aria-pressed="true"]{background:var(--cyan);border-color:var(--cyan);color:#04131f}
.filter-btn:focus-visible{outline-offset:2px}

/* ===== 09 media frame ===== */
.media-frame{
  position:relative;display:block;overflow:hidden;
  border-radius:var(--radius-md);
  border:1px solid rgba(0,229,255,.18);
  background:
    radial-gradient(120% 90% at 82% 0%,rgba(0,229,255,.24),transparent 62%),
    linear-gradient(150deg,var(--ink-700),var(--ink-900));
  min-height:180px;
}
.media-frame::after{
  content:"";position:absolute;inset:0;pointer-events:none;
  background:repeating-linear-gradient(115deg,rgba(0,229,255,.08) 0 1px,transparent 1px 17px);
}
.media-frame img,.media-frame__img{
  display:block;width:100%;height:100%;
  aspect-ratio:16/9;object-fit:cover;
  filter:saturate(1.06) contrast(1.05);
}
.media-frame__caption{
  position:absolute;left:14px;bottom:14px;right:14px;z-index:1;
  font:500 11.5px/1.5 var(--font-mono);letter-spacing:.1em;color:var(--cyan-soft);
  text-shadow:0 1px 10px rgba(0,0,0,.7);
}

/* ===== 10 prose & breadcrumbs ===== */
.prose{max-width:70ch;font-size:16.5px;line-height:1.82;color:rgba(244,247,251,.9)}
.prose p{margin-bottom:1.1em;max-width:none}
.prose h2{font-size:clamp(1.2rem,2vw,1.55rem);margin:1.8em 0 .6em;color:var(--cyan-soft)}
.prose h3{font-size:1.1rem;margin:1.4em 0 .5em}
.prose ul{margin:0 0 1.1em;display:grid;gap:.4em;padding-left:1.1em}
.prose li{position:relative;padding-left:.9em}
.prose li::before{content:"—";position:absolute;left:0;color:var(--cyan)}
.prose strong{color:var(--paper)}
.prose a{color:var(--cyan);text-underline-offset:3px}
.prose--light{background:var(--paper);color:#16283f;max-width:none;padding:clamp(22px,4vw,44px);border-radius:var(--radius-md)}
.prose--light h2,.prose--light h3{color:#0B1F3A}
.prose--light strong{color:#071528}
.prose--light a{color:#0B62C4}
.prose--light li::before{color:var(--violet)}
.breadcrumbs{
  display:flex;flex-wrap:wrap;align-items:center;gap:8px;
  font:500 12px/1.6 var(--font-mono);letter-spacing:.08em;color:var(--silver);
  padding-block:clamp(14px,2vw,22px);
}
.breadcrumbs__list{display:flex;flex-wrap:wrap;align-items:center;gap:8px}
.breadcrumbs__link{color:var(--silver);text-decoration:none;border-bottom:1px solid transparent;transition:color .16s var(--ease),border-color .16s var(--ease)}
.breadcrumbs__link:hover,.breadcrumbs__link:focus-visible{color:var(--cyan);border-color:var(--cyan)}
.breadcrumbs__sep{color:rgba(174,185,201,.5)}
.breadcrumbs [aria-current="page"]{color:var(--cyan)}

/* ===== 11 reveal ===== */
[data-reveal]{opacity:0;transform:translateY(14px);transition:opacity .28s var(--ease),transform .28s var(--ease)}
[data-reveal].is-visible{opacity:1;transform:none}

/* ===== 12 responsive ===== */
@media (max-width:1180px){
  .nav__link{padding:11px 6px 13px;font-size:14px}
  .nav__link::after{left:6px;right:6px}
}
@media (max-width:1080px){
  .nav-toggle{display:inline-flex}
  .nav__cta{
    display:inline-flex;align-items:center;justify-content:center;
    margin-top:18px;padding:14px 18px;
    background:var(--orange);color:#150800;
    font:700 15px/1 var(--font-body);text-decoration:none;
    clip-path:polygon(11px 0,100% 0,calc(100% - 11px) 100%,0 100%);
  }
  .nav{
    position:fixed;top:0;right:0;bottom:0;z-index:80;
    width:min(370px,88vw);margin:0;
    padding:clamp(88px,16vh,130px) 26px 36px;
    background:linear-gradient(160deg,var(--ink-900) 0%,var(--ink-800) 56%,var(--ink-700) 100%);
    border-left:1px solid rgba(0,229,255,.34);
    box-shadow:-30px 0 60px -40px rgba(0,0,0,.95);
    overflow-y:auto;
    transform:translateX(103%);visibility:hidden;
    transition:transform .22s var(--ease),visibility .22s var(--ease);
  }
  .nav::before{
    content:"";position:absolute;inset:0;pointer-events:none;
    background:repeating-linear-gradient(115deg,rgba(0,229,255,.06) 0 1px,transparent 1px 16px);
  }
  .arena-header[data-open="true"] .nav{transform:translateX(0);visibility:visible}
  .nav__list{position:relative;flex-direction:column;align-items:stretch;gap:0}
  .nav__link{
    justify-content:flex-start;padding:17px 4px;font-size:17px;
    border-bottom:1px solid var(--line-soft);
  }
  .nav__link::after{left:0;right:auto;bottom:-1px;width:0;height:2px;transform:none;transition:width .2s var(--ease)}
  .nav__link:hover::after,.nav__link:focus-visible::after,.nav__link[aria-current="page"]::after{width:42px;transform:none}
  .footer__grid{grid-template-columns:minmax(0,1fr)}
}
@media (max-width:860px){
  .footer__cols{grid-template-columns:repeat(2,minmax(0,1fr));gap:24px}
  .grid--3,.grid--split{grid-template-columns:minmax(0,1fr)}
}
@media (max-width:760px){
  .strip__utility{display:none}
  .strip{min-height:34px;font-size:11px}
  .strip__note{white-space:nowrap;overflow:hidden;text-overflow:ellipsis;max-width:100%}
  .bar{min-height:66px;gap:12px}
  .brand__glyph{width:40px;height:40px;font-size:18px}
  .brand__name{font-size:22px}
  .brand__sub{font-size:9px;letter-spacing:.18em}
  .grid--2{grid-template-columns:minmax(0,1fr)}
  .section__head{grid-template-columns:minmax(0,1fr);gap:10px}
  .section__index{font-size:clamp(2rem,9vw,3rem)}
}
@media (max-width:520px){
  .bar__actions .btn--accent{display:none}
  .nav-toggle__label{display:none}
  .nav-toggle{padding:0 12px}
  .footer__cols{grid-template-columns:minmax(0,1fr)}
  .footer__legal{flex-direction:column;align-items:flex-start}
}
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation-duration:.001ms !important;animation-iteration-count:1 !important;transition-duration:.001ms !important;scroll-behavior:auto !important}
  [data-reveal]{opacity:1;transform:none}
  .scroll-progress__fill{transition:none}
}