/* =====================================================================
   OG视讯厅 · 共享样式 /assets/site.css
   深炭基色场 + 轨道导航 + 玻璃浮层 + 编辑化排版
   ===================================================================== */

:root{
  --ink-900:#0E1013;
  --ink-800:#1A1310;
  --ink-700:#141619;
  --paper:#F2E9DC;
  --cyan:#35E5D6;
  --violet:#8A5CFF;
  --amber:#F0B429;
  --orange:#E4572E;
  --gray:#9AA3AD;
  --line:#3C4A55;
  --glass:rgba(242,233,220,.08);
  --glass-line:rgba(53,229,214,.28);
  --hair:rgba(60,74,85,.55);
  --rail-w:250px;
  --shell-max:1280px;
  --pad-x:clamp(18px,4vw,40px);
  --font-serif:"Noto Serif SC","Source Han Serif SC","Songti SC","SimSun",serif;
  --font-sans:"Noto Sans SC","Source Han Sans SC","PingFang SC","Microsoft YaHei",system-ui,sans-serif;
  --font-mono:"IBM Plex Mono","JetBrains Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --ease:cubic-bezier(.2,.7,.3,1);
  --progress:0;
}

/* ---------- 1. 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,pre{margin:0}
ul,ol{padding:0;list-style:none}
img,svg,video{display:block;max-width:100%}
button{font:inherit;color:inherit;background:none;border:0}
a{color:inherit}
table{border-collapse:collapse;width:100%}
:focus-visible{outline:2px solid var(--cyan);outline-offset:3px;border-radius:2px}

/* ---------- 2. 基底与中文排版 ---------- */
body{
  background:var(--ink-900);
  color:var(--paper);
  font-family:var(--font-sans);
  font-size:16px;
  line-height:1.75;
  overflow-x:hidden;
  -webkit-font-smoothing:antialiased;
}
body[data-nav-open="true"]{overflow:hidden}
#main-content{display:block;scroll-margin-top:84px}
p{max-width:74ch}
strong{color:var(--paper);font-weight:600}
::selection{background:rgba(53,229,214,.3);color:#f6fffe}

.display-title{
  font-family:var(--font-sans);
  font-weight:800;
  font-size:clamp(44px,9vw,96px);
  line-height:.96;
  letter-spacing:-.02em;
  color:var(--paper);
}
.editorial-title{
  font-family:var(--font-serif);
  font-weight:700;
  font-size:clamp(28px,4.2vw,48px);
  line-height:1.22;
  letter-spacing:.01em;
  max-width:24ch;
}
.section-title{
  font-family:var(--font-serif);
  font-weight:700;
  font-size:clamp(21px,2.4vw,28px);
  line-height:1.35;
  max-width:26ch;
}
.lede{
  font-size:clamp(16px,1.6vw,18px);
  line-height:1.8;
  color:#CDD4DA;
  max-width:52ch;
}
.eyebrow{
  display:flex;
  align-items:center;
  gap:10px;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--cyan);
}
.eyebrow::before{content:"";width:26px;height:1px;background:var(--cyan);box-shadow:0 0 10px rgba(53,229,214,.7)}
.note{
  font-size:14px;
  line-height:1.7;
  color:var(--gray);
  border-left:2px solid var(--amber);
  padding-left:14px;
  max-width:46ch;
}
.rule{
  height:1px;
  border:0;
  margin:0;
  background:linear-gradient(90deg,rgba(53,229,214,.55),rgba(138,92,255,.35) 45%,rgba(60,74,85,0) 100%);
}

/* ---------- 3. 布局骨架 ---------- */
.shell{
  width:100%;
  max-width:var(--shell-max);
  margin-inline:auto;
  padding-inline:var(--pad-x);
}
.section{
  padding-block:clamp(46px,7vw,96px);
  border-top:1px solid rgba(60,74,85,.42);
}
.section:first-of-type{border-top:0}
.section--warm{background:linear-gradient(180deg,var(--ink-800),var(--ink-700) 60%,var(--ink-900))}
.section--cool{background:linear-gradient(180deg,#101319,#0E1013)}
.section-head{
  display:flex;
  flex-wrap:wrap;
  align-items:flex-end;
  gap:14px 28px;
  margin-bottom:clamp(24px,3vw,40px);
}
.grid-8{
  display:grid;
  grid-template-columns:repeat(8,minmax(0,1fr));
  gap:24px;
}
.span-3{grid-column:span 3}
.span-4{grid-column:span 4}
.span-5{grid-column:span 5}
.span-8{grid-column:1/-1}
.bleed{
  margin-inline:calc(-1 * var(--pad-x));
  padding-inline:var(--pad-x);
}

/* ---------- 4. 头部：轨道导航 ---------- */
.skip-link{
  position:fixed;
  top:0;
  left:0;
  z-index:300;
  transform:translateY(-140%);
  background:var(--cyan);
  color:#052B27;
  font-family:var(--font-mono);
  font-size:13px;
  letter-spacing:.06em;
  padding:10px 18px;
  text-decoration:none;
  border-radius:0 0 4px 0;
  transition:transform .2s var(--ease);
}
.skip-link:focus{transform:translateY(0)}

.site-header{
  position:sticky;
  top:0;
  z-index:80;
  background:linear-gradient(180deg,#15171C,var(--ink-900));
  border-bottom:1px solid rgba(53,229,214,.18);
  color:var(--paper);
  font-family:var(--font-sans);
}

.topbar{
  position:relative;
  z-index:2;
  display:flex;
  align-items:center;
  gap:12px;
  min-height:64px;
  padding:10px var(--pad-x);
  background:linear-gradient(180deg,#15171C,var(--ink-900));
}
.brand{
  display:flex;
  align-items:center;
  gap:12px;
  min-width:0;
  text-decoration:none;
  color:inherit;
}
.brand__mark{
  flex:0 0 auto;
  width:44px;
  height:44px;
  display:grid;
  place-items:center;
  font-family:var(--font-mono);
  font-size:15px;
  font-weight:600;
  letter-spacing:.02em;
  color:var(--cyan);
  border:1px solid rgba(53,229,214,.5);
  border-radius:4px;
  background:linear-gradient(140deg,rgba(53,229,214,.16),rgba(138,92,255,.18));
  box-shadow:inset 0 0 0 1px rgba(14,16,19,.65),0 0 22px rgba(53,229,214,.16);
}
.brand__text{display:flex;flex-direction:column;min-width:0}
.brand__name{
  font-family:var(--font-serif);
  font-weight:700;
  font-size:18px;
  line-height:1.3;
  letter-spacing:.01em;
}
.brand__line{
  font-size:12px;
  line-height:1.5;
  letter-spacing:.06em;
  color:var(--gray);
  white-space:nowrap;
  overflow:hidden;
  text-overflow:ellipsis;
}
.topbar__meta{
  display:none;
  align-items:center;
  gap:8px;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.1em;
  color:var(--gray);
}
.topbar__dot{
  width:6px;
  height:6px;
  border-radius:50%;
  background:var(--cyan);
  box-shadow:0 0 10px var(--cyan);
  animation:pulse 2.6s infinite ease-in-out;
}
@keyframes pulse{0%,100%{opacity:1}50%{opacity:.35}}

.nav-toggle{
  margin-left:auto;
  display:inline-flex;
  align-items:center;
  gap:9px;
  padding:9px 13px;
  border:1px solid rgba(53,229,214,.4);
  border-radius:3px;
  background:rgba(242,233,220,.06);
  color:var(--paper);
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.12em;
  cursor:pointer;
  transition:border-color .18s var(--ease),color .18s var(--ease),background .18s var(--ease);
}
.nav-toggle:hover{border-color:var(--cyan);color:var(--cyan)}
.nav-toggle__icon{display:flex;flex-direction:column;gap:5px;width:16px}
.nav-toggle__bar{display:block;height:1px;background:currentColor}
.nav-toggle__label{line-height:1}

.site-nav{
  position:fixed;
  inset:0 auto 0 0;
  z-index:1;
  width:min(340px,86vw);
  display:flex;
  flex-direction:column;
  gap:0;
  padding:76px 0 26px;
  overflow-y:auto;
  background:
    radial-gradient(120% 55% at 0% 0%,rgba(138,92,255,.2),transparent 62%),
    linear-gradient(180deg,#14161B,var(--ink-900) 70%);
  border-right:1px solid rgba(53,229,214,.22);
  box-shadow:0 0 70px rgba(0,0,0,.72);
  transform:translateX(-102%);
  opacity:0;
  visibility:hidden;
  transition:transform .22s var(--ease),opacity .22s var(--ease),visibility .22s;
}
.site-header[data-open="true"] .site-nav{transform:none;opacity:1;visibility:visible}
.site-nav__hint{
  font-size:12px;
  line-height:1.7;
  letter-spacing:.04em;
  color:var(--gray);
  padding:0 22px 14px;
  max-width:32ch;
}
.nav-list{margin:0;padding:0}
.nav-list__item{display:block}
.nav-link{
  display:grid;
  grid-template-columns:34px 1fr;
  align-items:baseline;
  gap:6px;
  padding:12px 22px;
  border-left:2px solid transparent;
  color:var(--paper);
  text-decoration:none;
  font-size:15.5px;
  letter-spacing:.02em;
  transition:color .18s var(--ease),background .18s var(--ease),border-color .18s var(--ease);
}
.nav-link__index{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.08em;
  color:var(--line);
}
.nav-link__label{display:block}
.nav-link:hover{
  color:var(--cyan);
  background:rgba(242,233,220,.05);
  border-left-color:rgba(53,229,214,.4);
}
.nav-link[aria-current="page"]{
  color:var(--cyan);
  background:linear-gradient(90deg,rgba(53,229,214,.16),rgba(53,229,214,0) 78%);
  border-left-color:var(--cyan);
  box-shadow:inset 0 0 26px rgba(53,229,214,.09);
}
.nav-link[aria-current="page"] .nav-link__index{color:var(--amber)}

.nav-foot{
  margin-top:auto;
  display:flex;
  flex-direction:column;
  gap:8px;
  padding:18px 22px 4px;
  border-top:1px solid var(--hair);
}
.nav-foot__link{
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.12em;
  color:var(--gray);
  text-decoration:none;
  padding:4px 0;
  transition:color .18s var(--ease);
}
.nav-foot__link:hover{color:var(--cyan)}
.nav-foot .cta{width:100%;margin-top:10px}

/* 轨道进度光带（移动端为顶部横向，桌面为纵向） */
.rail-progress{
  position:absolute;
  left:0;
  right:0;
  bottom:-1px;
  top:auto;
  height:2px;
  width:auto;
  background:rgba(60,74,85,.35);
  pointer-events:none;
  z-index:3;
}
.rail-progress__bar{
  display:block;
  width:100%;
  height:100%;
  transform-origin:left center;
  transform:scaleX(var(--progress,0));
  background:linear-gradient(90deg,var(--cyan),var(--violet));
  box-shadow:0 0 14px rgba(53,229,214,.65);
}

.nav-scrim{
  position:fixed;
  inset:0;
  z-index:70;
  background:rgba(8,9,11,.72);
  opacity:0;
  visibility:hidden;
  transition:opacity .22s var(--ease),visibility .22s;
}
.nav-scrim[data-visible="true"]{opacity:1;visibility:visible}

/* ---------- 5. 按钮 ---------- */
.cta{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:8px;
  padding:11px 18px;
  border:1px solid transparent;
  border-radius:3px;
  font-family:var(--font-mono);
  font-size:13px;
  letter-spacing:.1em;
  text-decoration:none;
  cursor:pointer;
  transition:color .18s var(--ease),border-color .18s var(--ease),background .18s var(--ease),box-shadow .18s var(--ease);
}
.cta--primary{
  color:var(--cyan);
  border-color:rgba(53,229,214,.55);
  background:linear-gradient(120deg,rgba(53,229,214,.16),rgba(138,92,255,.2));
  box-shadow:inset 0 0 0 1px rgba(14,16,19,.5),0 0 22px rgba(53,229,214,.14);
}
.cta--primary:hover{
  color:#EAFFFC;
  border-color:var(--cyan);
  background:linear-gradient(120deg,rgba(53,229,214,.28),rgba(138,92,255,.3));
}
.cta--ghost{
  color:var(--gray);
  border-color:var(--hair);
}
.cta--ghost:hover{color:var(--paper);border-color:var(--amber)}

/* ---------- 6. 页脚 ---------- */
.site-footer{
  position:relative;
  padding-block:clamp(42px,6vw,64px) 26px;
  background:linear-gradient(180deg,var(--ink-800),var(--ink-700) 42%,var(--ink-900));
  border-top:1px solid rgba(53,229,214,.18);
  color:var(--paper);
  font-family:var(--font-sans);
}
.site-footer::before{
  content:"";
  position:absolute;
  left:0;
  right:0;
  top:0;
  height:1px;
  background:linear-gradient(90deg,transparent,rgba(53,229,214,.7),rgba(138,92,255,.6),transparent);
}
.footer-grid{
  display:grid;
  grid-template-columns:1fr;
  gap:32px 24px;
}
.footer-brand{display:flex;flex-direction:column;gap:8px}
.footer-brand__name{
  font-family:var(--font-serif);
  font-weight:700;
  font-size:20px;
  line-height:1.3;
}
.footer-brand__line{
  font-size:13px;
  letter-spacing:.06em;
  color:var(--gray);
}
.footer-col{display:block}
.footer-col__title{
  margin-bottom:14px;
  font-family:var(--font-mono);
  font-weight:500;
  font-size:11px;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--cyan);
}
.footer-col__list{display:flex;flex-direction:column;gap:2px}
.footer-link{
  display:inline-block;
  padding:5px 0;
  color:var(--gray);
  font-size:15px;
  text-decoration:none;
  border-bottom:1px solid transparent;
  transition:color .18s var(--ease),border-color .18s var(--ease);
}
.footer-link:hover{color:var(--paper);border-bottom-color:rgba(53,229,214,.6)}
.footer-contact__list{display:grid;gap:10px}
.footer-contact__item{display:flex;flex-direction:column;gap:2px}
.footer-contact__key{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.14em;
  color:var(--gray);
}
.footer-contact__val{
  font-size:14px;
  line-height:1.65;
  color:var(--paper);
  word-break:break-word;
  max-width:34ch;
}
.footer-base{
  margin-top:clamp(34px,4vw,50px);
  padding-top:20px;
  border-top:1px dashed rgba(60,74,85,.85);
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:12px 28px;
}
.footer-legal{
  font-size:13px;
  line-height:1.7;
  color:var(--gray);
  max-width:58ch;
}
.footer-sign{display:flex;flex-wrap:wrap;align-items:center;gap:12px}
.footer-icp{
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.04em;
  color:var(--gray);
  border:1px solid var(--hair);
  border-radius:2px;
  padding:4px 10px;
}
.footer-copy{font-family:var(--font-mono);font-size:12px;color:var(--gray)}

/* ---------- 7. 内容组件 ---------- */
.panel{border-radius:4px;padding:clamp(20px,3vw,34px)}
.panel--paper{
  background:var(--paper);
  color:#1A1310;
  border:1px solid rgba(26,19,16,.14);
  box-shadow:0 20px 50px rgba(0,0,0,.35);
}
.panel--paper h2,.panel--paper h3,.panel--paper h4{color:#1A1310}
.panel--paper a{color:#A83A15;text-decoration:underline;text-underline-offset:3px}
.panel--paper .note{color:#5C4C40;border-left-color:var(--orange)}
.panel--glass{
  background:var(--glass);
  border:1px solid var(--glass-line);
  backdrop-filter:blur(12px);
  -webkit-backdrop-filter:blur(12px);
  border-radius:4px;
}

.data-strip{
  display:grid;
  grid-template-columns:repeat(auto-fit,minmax(150px,1fr));
  gap:1px;
  background:var(--hair);
  border:1px solid var(--hair);
  border-radius:4px;
  overflow:hidden;
}
.data-strip__cell{
  background:var(--ink-700);
  padding:18px 16px 16px;
}
.data-strip__value{
  display:block;
  font-family:var(--font-mono);
  font-weight:500;
  font-size:clamp(24px,3vw,34px);
  line-height:1.1;
  color:var(--amber);
}
.data-strip__unit{
  font-family:var(--font-mono);
  font-size:.5em;
  color:var(--gray);
  margin-left:5px;
}
.data-strip__label{
  display:block;
  margin-top:8px;
  font-size:13px;
  letter-spacing:.06em;
  color:var(--gray);
}
.stat{display:flex;flex-direction:column;gap:4px}
.stat__value{
  font-family:var(--font-mono);
  font-weight:500;
  font-size:clamp(26px,3.6vw,42px);
  line-height:1;
  color:var(--amber);
}
.stat__unit{font-family:var(--font-mono);font-size:14px;color:var(--gray);margin-left:6px}
.stat__label{font-size:13px;letter-spacing:.08em;color:var(--gray)}

.index-panel{
  position:sticky;
  top:26px;
  padding:18px;
  background:var(--glass);
  border:1px solid var(--glass-line);
  backdrop-filter:blur(12px);
  -webkit-backdrop-filter:blur(12px);
  border-radius:4px;
}
.index-panel__title{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--cyan);
  margin-bottom:12px;
}
.index-panel__list{display:flex;flex-direction:column;gap:2px}
.index-link{
  display:block;
  padding:6px 0 6px 12px;
  border-left:1px solid #3C4A55;
  font-size:14px;
  color:var(--gray);
  text-decoration:none;
  transition:color .18s var(--ease),border-color .18s var(--ease);
}
.index-link:hover{color:var(--cyan);border-left-color:var(--cyan)}

.expand-group{
  border:1px solid var(--hair);
  border-radius:4px;
  background:rgba(242,233,220,.03);
  transition:border-color .18s var(--ease),background .18s var(--ease);
}
.expand-group + .expand-group{margin-top:10px}
.expand-group[data-open="true"]{
  border-color:rgba(53,229,214,.6);
  background:rgba(53,229,214,.06);
}
.expand-group__summary{
  display:flex;
  align-items:center;
  gap:12px;
  width:100%;
  padding:16px 18px;
  text-align:left;
  font-size:16px;
  line-height:1.6;
  color:var(--paper);
  cursor:pointer;
}
.expand-group__summary::after{
  content:"+";
  margin-left:auto;
  font-family:var(--font-mono);
  font-size:18px;
  color:var(--cyan);
}
.expand-group[data-open="true"] .expand-group__summary::after{content:"−"}
.expand-group__summary:hover{color:var(--cyan)}
.expand-group__body{
  padding:0 18px 18px;
  font-size:15px;
  line-height:1.8;
  color:#C3CBD2;
}
.expand-group__body[hidden]{display:none}

.tab-bar{
  display:flex;
  flex-wrap:wrap;
  gap:8px;
  padding-bottom:12px;
  border-bottom:1px solid var(--hair);
}
.tab-btn{
  padding:8px 14px;
  border:1px solid var(--hair);
  border-radius:999px;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.08em;
  color:var(--gray);
  cursor:pointer;
  transition:color .18s var(--ease),border-color .18s var(--ease),background .18s var(--ease);
}
.tab-btn:hover{color:var(--paper);border-color:var(--gray)}
.tab-btn[aria-selected="true"],
.tab-btn[data-active="true"]{
  color:var(--cyan);
  border-color:var(--cyan);
  background:rgba(53,229,214,.14);
}
.chip{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:4px 10px;
  border:1px solid rgba(138,92,255,.5);
  border-radius:999px;
  background:rgba(138,92,255,.12);
  color:#C6AEFF;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.06em;
}
.badge{
  display:inline-block;
  padding:3px 8px;
  border:1px solid rgba(228,87,46,.6);
  background:rgba(228,87,46,.1);
  color:var(--orange);
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.14em;
}
.timeline{
  display:grid;
  gap:26px;
  padding-left:22px;
  border-left:1px solid rgba(60,74,85,.75);
}
.timeline__item{position:relative}
.timeline__item::before{
  content:"";
  position:absolute;
  left:-27px;
  top:9px;
  width:9px;
  height:9px;
  border-radius:50%;
  background:var(--cyan);
  box-shadow:0 0 12px rgba(53,229,214,.8);
}
.timeline__mark{
  display:block;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.1em;
  color:var(--amber);
  margin-bottom:4px;
}
.breadcrumbs{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.06em;
  color:var(--gray);
}
.breadcrumbs__link{
  color:var(--gray);
  text-decoration:none;
  border-bottom:1px solid transparent;
}
.breadcrumbs__link:hover{color:var(--cyan);border-bottom-color:rgba(53,229,214,.6)}
.breadcrumbs__sep{color:var(--line)}
.breadcrumbs__current{color:var(--paper)}

/* 图像容器：供页面阶段放置图片 */
.media{display:block;margin:0}
.media__frame{
  position:relative;
  overflow:hidden;
  border:1px solid rgba(53,229,214,.22);
  border-radius:4px;
  background:
    radial-gradient(90% 70% at 20% 10%,rgba(138,92,255,.22),transparent 60%),
    linear-gradient(140deg,#161A21,var(--ink-900) 58%,var(--ink-800));
}
.media__frame::after{
  content:"";
  position:absolute;
  inset:0;
  pointer-events:none;
  background-image:
    linear-gradient(rgba(53,229,214,.07) 1px,transparent 1px),
    linear-gradient(90deg,rgba(53,229,214,.07) 1px,transparent 1px);
  background-size:34px 34px;
}
.media__img{width:100%;height:100%;object-fit:cover}
.media--16x9 .media__frame{aspect-ratio:16/9}
.media--4x3 .media__frame{aspect-ratio:4/3}
.media--1x1 .media__frame{aspect-ratio:1/1}
.media--21x9 .media__frame{aspect-ratio:21/9}
.media--tall .media__frame{aspect-ratio:3/4}
.media--wide{margin-inline:calc(-1 * var(--pad-x))}
.media__caption{
  margin-top:10px;
  font-size:13px;
  line-height:1.65;
  color:var(--gray);
  max-width:62ch;
}

/* ---------- 8. 动效协议 ---------- */
[data-reveal]{
  opacity:0;
  transform:translateY(12px);
  transition:opacity .5s var(--ease),transform .5s var(--ease);
}
[data-reveal].is-visible{opacity:1;transform:none}

/* ---------- 9. 响应式 ---------- */
@media (max-width:479px){
  .brand__line{display:none}
}
@media (min-width:700px){
  .topbar__meta{display:flex;margin-left:22px}
}
@media (min-width:640px) and (max-width:959px){
  .footer-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer-brand,.footer-contact{grid-column:span 2}
}
@media (max-width:959px){
  .grid-8{grid-template-columns:repeat(4,minmax(0,1fr));gap:18px}
  .span-3,.span-4,.span-5{grid-column:1/-1}
  .nav-scrim{display:block}
}
@media (max-width:599px){
  .grid-8{grid-template-columns:1fr;gap:14px}
  .span-3,.span-4,.span-5,.span-8{grid-column:1/-1}
  .data-strip{grid-template-columns:repeat(2,minmax(0,1fr))}
}

/* 桌面：左侧常驻轨道 */
@media (min-width:960px){
  body{padding-left:var(--rail-w);padding-top:0}
  .site-header{
    position:fixed;
    inset:0 auto 0 0;
    width:var(--rail-w);
    height:100vh;
    height:100dvh;
    display:flex;
    flex-direction:column;
    border-bottom:0;
    border-right:1px solid rgba(53,229,214,.18);
    padding:24px 0 20px;
    background:
      radial-gradient(120% 55% at 0% 0%,rgba(138,92,255,.18),transparent 60%),
      linear-gradient(180deg,#12141A,var(--ink-900) 62%,#0B0D10);
    overflow:hidden;
  }
  .topbar{
    flex-direction:column;
    align-items:flex-start;
    gap:14px;
    padding:0 22px 18px;
    background:none;
    min-height:0;
  }
  .topbar__meta{margin-left:0;order:3}
  .nav-toggle{display:none}
  .site-nav{
    position:static;
    inset:auto;
    width:auto;
    flex:1 1 auto;
    min-height:0;
    padding:4px 0 0;
    transform:none;
    opacity:1;
    visibility:visible;
    background:none;
    border-right:0;
    box-shadow:none;
    overflow-y:auto;
    transition:none;
  }
  .nav-foot{margin-top:auto}
  .rail-progress{
    position:absolute;
    left:auto;
    right:0;
    top:0;
    bottom:0;
    width:2px;
    height:auto;
    background:rgba(60,74,85,.45);
    z-index:3;
  }
  .rail-progress__bar{
    width:100%;
    height:100%;
    transform-origin:center top;
    transform:scaleY(var(--progress,0));
    background:linear-gradient(180deg,var(--cyan),var(--violet));
  }
  .nav-scrim{display:none}
  .footer-grid{
    grid-template-columns:repeat(12,minmax(0,1fr));
    gap:36px 24px;
  }
  .footer-brand{grid-column:span 3}
  .footer-col{grid-column:span 2}
  .footer-contact{grid-column:span 3}
}

/* ---------- 10. 无障碍与降级 ---------- */
@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}
  .rail-progress__bar{transition:none}
}