/* ===== 全站赛场 · 共享样式 /assets/site.css ===== */

/* --- reset --- */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body,h1,h2,h3,h4,h5,p,ul,ol,li,figure,blockquote,dl,dd{margin:0}
ul,ol{padding:0;list-style:none}
a{color:inherit;text-decoration:none}
img,svg{max-width:100%;display:block}
button{font:inherit;color:inherit;background:none;border:0;cursor:pointer}
table{border-collapse:collapse;width:100%}

/* --- variables --- */
:root{
  --space-0:#050912;
  --panel:#0B1420;
  --raise:#14202F;
  --line:#26364A;
  --line-soft:rgba(38,54,74,.55);
  --muted:#8FA0B4;
  --ink:#E8EEF5;
  --signal:#25E3B6;
  --signal-deep:#12A98A;
  --amber:#FF6A2B;
  --signal-wash:#0D2B27;
  --header-h:74px;
  --cut:16px;
  --cut-lg:24px;
  --font-display:"Barlow Condensed","Oswald","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  --font-body:"Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  --font-mono:ui-monospace,SFMono-Regular,"Cascadia Mono","Consolas","Liberation Mono",monospace;
  --ease:cubic-bezier(.2,.7,.3,1);
}

/* --- base --- */
body{
  background-color:var(--space-0);
  background-image:
    radial-gradient(circle at 84% -12%,rgba(37,227,182,.15),transparent 46%),
    radial-gradient(circle at 4% 8%,rgba(255,106,43,.10),transparent 40%),
    linear-gradient(180deg,rgba(11,20,32,.75),rgba(5,9,18,0) 62%);
  background-repeat:no-repeat;
  color:var(--ink);
  font-family:var(--font-body);
  font-size:16px;
  font-weight:400;
  line-height:1.75;
  letter-spacing:.005em;
  min-height:100vh;
  overflow-x:hidden;
}
h1,h2,h3,h4,h5{
  font-family:var(--font-display);
  font-weight:800;
  line-height:1.14;
  letter-spacing:-.02em;
  font-stretch:87.5%;
}
h1{font-size:clamp(44px,9vw,128px)}
h2{font-size:clamp(26px,3.4vw,40px)}
h3{font-size:clamp(19px,2vw,24px)}
p{font-size:clamp(15.5px,1.05vw,16.5px)}
.mono,.num{font-family:var(--font-mono);font-variant-numeric:tabular-nums;letter-spacing:.02em}
.muted{color:var(--muted)}

:focus-visible{outline:2px solid var(--signal);outline-offset:3px;border-radius:1px}

/* --- skip link --- */
.skip-link{
  position:fixed;top:10px;left:10px;z-index:200;
  padding:10px 16px;background:var(--signal);color:#04140F;
  font-family:var(--font-mono);font-size:13px;letter-spacing:.08em;
  clip-path:polygon(10px 0,100% 0,100% calc(100% - 10px),calc(100% - 10px) 100%,0 100%,0 10px);
  transform:translateY(-160%);
  transition:transform .18s var(--ease);
}
.skip-link:focus-visible{transform:translateY(0)}

/* --- container --- */
.container{width:100%;max-width:1320px;margin-inline:auto;padding-inline:clamp(18px,4vw,44px)}

/* --- header --- */
.site-header{
  position:fixed;top:0;left:0;right:0;z-index:80;
  background:transparent;
  border-bottom:1px solid transparent;
  transition:background-color .2s var(--ease),border-color .2s var(--ease),backdrop-filter .2s var(--ease);
}
.site-header[data-scrolled="true"]{
  background:rgba(5,9,18,.93);
  -webkit-backdrop-filter:blur(10px);
  backdrop-filter:blur(10px);
  border-bottom-color:var(--line);
}
.header-shell{
  display:flex;align-items:center;gap:clamp(14px,3vw,40px);
  min-height:var(--header-h);
}
.brand{
  display:flex;align-items:baseline;gap:10px;flex:0 0 auto;
  padding-block:14px;
}
.brand__mark{
  font-family:var(--font-display);font-weight:800;
  font-size:clamp(19px,2.1vw,25px);letter-spacing:-.01em;
  color:var(--ink);
}
.brand__mark::after{
  content:"";display:inline-block;width:9px;height:9px;margin-left:9px;
  background:var(--signal);transform:translateY(-1px);
  clip-path:polygon(0 0,100% 0,100% 100%);
}
.brand__suffix{
  font-family:var(--font-mono);font-size:10.5px;letter-spacing:.16em;
  text-transform:uppercase;color:var(--muted);white-space:nowrap;
}
.scroll-rail{
  position:absolute;left:0;right:0;bottom:-1px;height:2px;
  overflow:hidden;pointer-events:none;
}
.scroll-rail__fill{
  display:block;height:100%;width:100%;
  transform:scaleX(0);transform-origin:0 50%;
  background:linear-gradient(90deg,var(--signal-deep),var(--signal) 62%,var(--amber));
}

/* --- navigation --- */
.site-nav{
  display:flex;align-items:center;justify-content:flex-end;
  gap:clamp(14px,2.4vw,34px);
  flex:1 1 auto;margin-left:auto;
}
.site-nav__list{display:flex;align-items:center;gap:clamp(10px,1.7vw,26px)}
.site-nav__link{
  position:relative;display:inline-flex;align-items:baseline;gap:6px;
  padding:9px 2px;font-size:14.5px;color:var(--muted);
  transition:color .16s var(--ease);
}
.site-nav__link::before{
  content:attr(data-idx);
  font-family:var(--font-mono);font-size:10px;letter-spacing:.08em;
  color:var(--line);transition:color .16s var(--ease);
}
.site-nav__link::after{
  content:"";position:absolute;left:0;right:0;bottom:3px;height:1px;
  background:var(--signal);transform:scaleX(0);transform-origin:0 50%;
  transition:transform .18s var(--ease);
}
.site-nav__link:hover{color:var(--ink)}
.site-nav__link:hover::before{color:var(--signal-deep)}
.site-nav__link:hover::after{transform:scaleX(1)}
.site-nav__link[aria-current="page"]{color:var(--signal)}
.site-nav__link[aria-current="page"]::before{color:var(--amber)}
.site-nav__link[aria-current="page"]::after{transform:scaleX(1);background:var(--amber)}
.nav-meta{display:flex;align-items:center;gap:14px}
.nav-meta__clock{
  font-family:var(--font-mono);font-size:11px;letter-spacing:.1em;
  color:var(--muted);white-space:nowrap;
}
.nav-meta__cta{flex:0 0 auto}

/* --- nav toggle --- */
.nav-toggle{
  display:none;align-items:center;gap:10px;
  padding:10px 14px;border:1px solid var(--line);
  background:var(--raise);color:var(--ink);
  clip-path:polygon(10px 0,100% 0,100% calc(100% - 10px),calc(100% - 10px) 100%,0 100%,0 10px);
  transition:border-color .18s var(--ease),color .18s var(--ease);
}
.nav-toggle__bars{position:relative;display:block;width:18px;height:2px;background:var(--ink)}
.nav-toggle__bars::before,
.nav-toggle__bars::after{
  content:"";position:absolute;left:0;width:18px;height:2px;background:var(--ink);
  transition:transform .18s var(--ease);
}
.nav-toggle__bars::before{top:-6px}
.nav-toggle__bars::after{top:6px}
.nav-toggle__label{font-family:var(--font-mono);font-size:11px;letter-spacing:.14em}
.nav-toggle[aria-expanded="true"]{border-color:var(--signal);color:var(--signal)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars{background:transparent}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before{background:var(--signal);transform:translateY(6px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after{background:var(--signal);transform:translateY(-6px) rotate(-45deg)}

/* --- buttons --- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:11px 16px;font-size:14px;font-weight:600;line-height:1.2;
  color:var(--ink);background:var(--panel);border:1px solid var(--line);
  clip-path:polygon(12px 0,100% 0,100% calc(100% - 12px),calc(100% - 12px) 100%,0 100%,0 12px);
  transition:background-color .18s var(--ease),border-color .18s var(--ease),color .18s var(--ease);
}
.btn:hover{background:var(--raise);border-color:var(--signal-deep);color:var(--signal)}
.btn--primary{
  color:var(--signal);border-color:var(--signal);
  background:linear-gradient(180deg,rgba(37,227,182,.12),rgba(37,227,182,0));
}
.btn--primary:hover{background:var(--signal);color:#04140F;border-color:var(--signal)}
.btn--ghost{background:transparent;color:var(--muted)}
.btn--ghost:hover{color:var(--ink);background:var(--raise)}
.btn--amber{color:var(--amber);border-color:var(--amber);background:linear-gradient(180deg,rgba(255,106,43,.12),rgba(255,106,43,0))}
.btn--amber:hover{background:var(--amber);color:#180702}

/* --- footer --- */
.site-footer{
  position:relative;margin-top:clamp(56px,8vw,120px);
  background:linear-gradient(180deg,rgba(11,20,32,.35),var(--panel) 46%);
  border-top:1px solid var(--line);
}
.footer-scan{
  height:2px;opacity:.55;
  background:repeating-linear-gradient(90deg,var(--signal) 0 22px,transparent 22px 34px,var(--amber) 34px 44px,transparent 44px 72px);
}
.footer-grid{
  display:grid;grid-template-columns:1.5fr repeat(3,minmax(0,1fr)) 1.6fr;
  gap:clamp(22px,3vw,44px);
  padding:clamp(38px,6vw,72px) 0 clamp(26px,4vw,44px);
}
.footer-brand__mark{
  font-family:var(--font-display);font-weight:800;font-size:26px;
  letter-spacing:-.01em;color:var(--ink);
}
.footer-brand__mark::after{
  content:"";display:inline-block;width:9px;height:9px;margin-left:9px;
  background:var(--amber);transform:translateY(-1px);
}
.footer-brand__suffix{margin-top:10px;font-size:14px;color:var(--muted);max-width:30ch}
.footer-brand__micro{
  margin-top:14px;font-family:var(--font-mono);font-size:11px;letter-spacing:.12em;
  color:var(--signal-deep);
}
.footer-col__title{
  margin-bottom:14px;font-family:var(--font-mono);font-size:11.5px;
  letter-spacing:.18em;text-transform:uppercase;color:var(--signal);font-weight:500;
}
.footer-col__list{display:flex;flex-direction:column;gap:2px}
.footer-col__link{
  display:inline-block;padding:6px 0;font-size:14.5px;color:var(--muted);
  transition:color .16s var(--ease),transform .16s var(--ease);
}
.footer-col__link:hover{color:var(--signal);transform:translateX(3px)}
.footer-col__link[aria-current="page"]{color:var(--ink);box-shadow:inset 0 -1px 0 var(--amber)}
.footer-contact__row{display:flex;align-items:center;gap:10px;padding:5px 0;flex-wrap:wrap}
.footer-contact__key{
  font-family:var(--font-mono);font-size:10.5px;letter-spacing:.14em;
  color:var(--line);min-width:32px;
}
.footer-contact__val{margin-top:8px;font-size:13.5px;color:var(--muted)}
.footer-contact__note{
  margin-top:12px;padding-left:12px;font-size:13px;color:var(--muted);
  border-left:2px solid var(--signal-deep);
}
.copy-chip{
  display:inline-flex;align-items:center;gap:8px;
  padding:5px 10px;font-family:var(--font-mono);font-size:12.5px;
  color:var(--ink);background:var(--raise);
  box-shadow:inset 0 0 0 1px var(--line);
  clip-path:polygon(8px 0,100% 0,100% calc(100% - 8px),calc(100% - 8px) 100%,0 100%,0 8px);
  transition:box-shadow .16s var(--ease),color .16s var(--ease),background-color .16s var(--ease);
}
.copy-chip:hover{color:var(--signal);box-shadow:inset 0 0 0 1px var(--signal-deep)}
.copy-chip[data-copied="true"]{
  color:var(--signal);background:var(--signal-wash);box-shadow:inset 0 0 0 1px var(--signal);
}
.footer-base{
  display:flex;flex-wrap:wrap;justify-content:space-between;gap:10px 26px;
  border-top:1px solid var(--line);padding:18px 0 30px;
  font-size:12.5px;color:var(--muted);
}
.footer-base__legal{font-family:var(--font-mono);letter-spacing:.06em}
.footer-base__micro{font-family:var(--font-mono);font-size:11.5px;letter-spacing:.08em;color:var(--line)}

/* --- to top --- */
.to-top{
  position:fixed;right:clamp(16px,3vw,28px);bottom:clamp(16px,3vw,28px);z-index:70;
  display:inline-flex;align-items:center;gap:8px;
  padding:10px 13px;font-family:var(--font-mono);font-size:11px;letter-spacing:.12em;
  color:var(--ink);background:rgba(11,20,32,.94);
  box-shadow:inset 0 0 0 1px var(--line);
  clip-path:polygon(10px 0,100% 0,100% calc(100% - 10px),calc(100% - 10px) 100%,0 100%,0 10px);
  transition:box-shadow .18s var(--ease),color .18s var(--ease);
}
.to-top[hidden]{display:none}
.to-top:hover{color:var(--signal);box-shadow:inset 0 0 0 1px var(--signal)}
.to-top__label{white-space:nowrap}

/* --- layout helpers --- */
.band{padding:clamp(48px,7vw,96px) 0;position:relative}
.band--first{padding-top:calc(var(--header-h) + clamp(48px,8vw,110px))}
.bento{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));gap:clamp(12px,1.4vw,20px)}
.bento > *{grid-column:span 12}

.cut-panel{
  position:relative;
  padding:clamp(20px,2.6vw,30px);
  background:var(--panel);
  box-shadow:inset 0 0 0 1px var(--line);
  clip-path:polygon(18px 0,100% 0,100% calc(100% - 18px),calc(100% - 18px) 100%,0 100%,0 18px);
  transition:background-color .2s var(--ease),box-shadow .2s var(--ease);
}
.cut-panel:hover{background:var(--raise);box-shadow:inset 0 0 0 1px #3a5271}
.cut-panel--focus{
  background:var(--signal-wash);
  box-shadow:inset 0 0 0 1px var(--signal);
}
.cut-panel--focus:hover{background:#10342f;box-shadow:inset 0 0 0 1px var(--signal)}

/* --- section head / eyebrow / stat --- */
.section-head{
  display:flex;flex-wrap:wrap;align-items:baseline;gap:10px 20px;
  margin-bottom:clamp(18px,2.4vw,30px);
}
.section-head__num{
  font-family:var(--font-mono);font-size:clamp(34px,5vw,56px);line-height:1;
  color:var(--signal);letter-spacing:-.03em;
}
.section-head__title{font-size:clamp(22px,3vw,34px);font-weight:800;color:var(--ink)}
.section-head__note{flex:1 1 260px;min-width:200px;font-size:14px;color:var(--muted)}
.eyebrow{
  display:inline-flex;align-items:center;gap:8px;
  font-family:var(--font-mono);font-size:11.5px;letter-spacing:.18em;
  text-transform:uppercase;color:var(--signal-deep);
}
.eyebrow::before{content:"";width:18px;height:1px;background:var(--amber)}
.stat{display:flex;flex-direction:column;gap:4px}
.stat__num{
  font-family:var(--font-mono);font-size:clamp(26px,3.4vw,40px);
  line-height:1.05;color:var(--ink);letter-spacing:-.02em;
}
.stat__num em{font-style:normal;color:var(--amber)}
.stat__label{font-size:13px;color:var(--muted)}

/* --- chips & tags --- */
.code-chip{
  display:inline-flex;align-items:center;gap:6px;
  padding:4px 10px;font-family:var(--font-mono);font-size:12px;letter-spacing:.08em;
  color:var(--signal);background:var(--signal-wash);
  box-shadow:inset 0 0 0 1px rgba(37,227,182,.35);
  clip-path:polygon(8px 0,100% 0,100% calc(100% - 8px),calc(100% - 8px) 100%,0 100%,0 8px);
}
.code-chip--amber{color:var(--amber);background:rgba(255,106,43,.1);box-shadow:inset 0 0 0 1px rgba(255,106,43,.4)}
.code-chip--mute{color:var(--muted);background:var(--raise);box-shadow:inset 0 0 0 1px var(--line)}
.tag-rail{display:flex;flex-wrap:wrap;gap:8px}
.tag{
  padding:6px 12px;font-size:13px;color:var(--muted);
  background:var(--panel);box-shadow:inset 0 0 0 1px var(--line);
  clip-path:polygon(8px 0,100% 0,100% calc(100% - 8px),calc(100% - 8px) 100%,0 100%,0 8px);
  transition:background-color .16s var(--ease),color .16s var(--ease),box-shadow .16s var(--ease);
}
.tag:hover{color:var(--ink);background:var(--raise)}
.tag[aria-pressed="true"]{color:#04140F;background:var(--signal);box-shadow:inset 0 0 0 1px var(--signal)}

/* --- breadcrumb --- */
.breadcrumb{
  display:flex;flex-wrap:wrap;align-items:center;gap:8px;
  font-family:var(--font-mono);font-size:12px;letter-spacing:.06em;color:var(--muted);
}
.breadcrumb__link{transition:color .16s var(--ease)}
.breadcrumb__link:hover{color:var(--signal)}
.breadcrumb__sep{color:var(--line)}
.breadcrumb__current{color:var(--ink)}

/* --- prose --- */
.prose{max-width:74ch}
.prose > * + *{margin-top:1.1em}
.prose h2{margin-top:2.2em;font-size:clamp(24px,2.6vw,32px)}
.prose h3{margin-top:1.8em;font-size:clamp(18px,1.8vw,21px);color:var(--ink)}
.prose p{color:#C6D2E0}
.prose ul,.prose ol{display:flex;flex-direction:column;gap:8px;padding-left:0}
.prose li{position:relative;padding-left:20px;color:#C6D2E0}
.prose li::before{
  content:"";position:absolute;left:0;top:.72em;width:8px;height:8px;
  background:var(--signal-deep);clip-path:polygon(0 0,100% 0,100% 100%);
}
.prose strong{color:var(--ink)}
.prose blockquote{
  padding:14px 20px;border-left:2px solid var(--signal);background:var(--panel);
  color:var(--muted);
}
.prose code{
  font-family:var(--font-mono);font-size:.9em;color:var(--signal);
  background:var(--raise);padding:2px 6px;
}
.link-signal{
  color:var(--signal);box-shadow:inset 0 -1px 0 var(--signal-deep);
  transition:box-shadow .16s var(--ease),color .16s var(--ease);
}
.link-signal:hover{color:var(--amber);box-shadow:inset 0 -1px 0 var(--amber)}

/* --- media frame --- */
.media-frame{
  position:relative;overflow:hidden;background:var(--panel);
  box-shadow:inset 0 0 0 1px var(--line);
  clip-path:polygon(20px 0,100% 0,100% calc(100% - 20px),calc(100% - 20px) 100%,0 100%,0 20px);
}
.media-frame__img{
  width:100%;height:100%;aspect-ratio:16/9;object-fit:cover;
  filter:saturate(.85) contrast(1.06) brightness(.94);
  transition:filter .2s var(--ease),transform .3s var(--ease);
}
.media-frame:hover .media-frame__img{filter:saturate(1) contrast(1.05) brightness(1)}
.media-frame--wide .media-frame__img{aspect-ratio:21/9}
.media-frame--tall .media-frame__img{aspect-ratio:4/5}
.media-frame__cap{
  margin-top:10px;font-family:var(--font-mono);font-size:11.5px;
  letter-spacing:.08em;color:var(--muted);
}

/* --- decorative --- */
.grid-veil{
  position:absolute;inset:0;pointer-events:none;opacity:.6;
  background-image:
    linear-gradient(rgba(38,54,74,.4) 1px,transparent 1px),
    linear-gradient(90deg,rgba(38,54,74,.4) 1px,transparent 1px);
  background-size:64px 64px;
  -webkit-mask-image:radial-gradient(ellipse at 50% 0%,#000,transparent 72%);
  mask-image:radial-gradient(ellipse at 50% 0%,#000,transparent 72%);
}
.trace{
  position:absolute;width:180px;height:1px;pointer-events:none;opacity:.55;
  background:linear-gradient(90deg,transparent,var(--signal));
  transform:rotate(-28deg);transform-origin:0 50%;
}
.trace--amber{background:linear-gradient(90deg,transparent,var(--amber))}
.node-dot{
  position:relative;display:inline-block;width:12px;height:12px;
  background:var(--signal);clip-path:polygon(50% 0,100% 50%,50% 100%,0 50%);
}
.node-dot::after{
  content:"";position:absolute;inset:-9px;opacity:0;
  box-shadow:inset 0 0 0 1px var(--signal);
  clip-path:polygon(50% 0,100% 50%,50% 100%,0 50%);
  transition:opacity .2s var(--ease);
}
.node-dot:hover::after{opacity:.75;animation:halo 1.2s var(--ease)}
@keyframes halo{
  0%{transform:scale(.7);opacity:.9}
  100%{transform:scale(1.5);opacity:0}
}

/* --- reveal --- */
html.js-on .reveal{opacity:0;transform:translateY(14px);transition:opacity .5s var(--ease),transform .5s var(--ease)}
html.js-on .reveal.is-in{opacity:1;transform:none}

/* --- responsive --- */
@media (min-width:760px){
  .span-6{grid-column:span 6}
  .span-12{grid-column:span 12}
  .footer-grid{grid-template-columns:1.4fr 1fr 1fr}
}
@media (min-width:1080px){
  .span-4{grid-column:span 4}
  .span-5{grid-column:span 5}
  .span-6{grid-column:span 6}
  .span-7{grid-column:span 7}
  .span-8{grid-column:span 8}
  .span-12{grid-column:span 12}
  .off-1{grid-column-start:2}
  .off-2{grid-column-start:3}
  .stagger > :nth-child(even){transform:translateY(16px)}
  .stagger > :nth-child(3n){transform:translateY(-8px)}
  .stagger .cut-panel:hover{transform:translateY(-2px)}
  .footer-grid{grid-template-columns:1.5fr repeat(3,minmax(0,1fr)) 1.7fr}
}
@media (max-width:1079px){
  .footer-grid{grid-template-columns:1fr 1fr;gap:28px 32px}
  .footer-brand,.footer-contact{grid-column:1 / -1}
}
@media (max-width:900px){
  :root{--header-h:66px}
  .nav-toggle{display:inline-flex;margin-left:auto}
  .site-nav{
    position:fixed;left:0;right:0;top:var(--header-h);
    display:none;flex-direction:column;align-items:stretch;gap:0;
    margin-left:0;padding:16px clamp(18px,4vw,44px) 26px;
    background:var(--panel);
    border-top:1px solid var(--line);border-bottom:1px solid var(--line);
    max-height:calc(100vh - var(--header-h));
    max-height:calc(100dvh - var(--header-h));
    overflow-y:auto;
    box-shadow:0 24px 40px rgba(0,0,0,.45);
  }
  .site-nav[data-open]{display:flex}
  .site-nav__list{flex-direction:column;align-items:stretch;gap:0}
  .site-nav__link{
    padding:15px 0;font-size:17px;justify-content:flex-start;
    border-bottom:1px solid var(--line-soft);
  }
  .site-nav__link::after{display:none}
  .site-nav__link[aria-current="page"]{box-shadow:inset 3px 0 0 var(--amber);padding-left:10px}
  .nav-meta{margin-top:18px;flex-direction:column;align-items:flex-start;gap:12px}
  .nav-meta__cta{width:100%}
  .brand__suffix{display:none}
}
@media (max-width:620px){
  .footer-grid{grid-template-columns:1fr}
  .footer-brand,.footer-contact{grid-column:auto}
  .footer-base{flex-direction:column;gap:8px}
  .to-top__label{display:none}
}

/* --- reduced motion --- */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
  html.js-on .reveal{opacity:1;transform:none}
  .node-dot:hover::after{animation:none}
}