/* =========================================================
   亿博赛场 · Site Kit 共享样式 /assets/site.css
   01 变量　02 重置与基础排版　03 布局容器与网格
   04 通用组件　05 图片容器　06 头部　07 页脚
   08 响应式　09 可访问性与动效降级
   ========================================================= */

/* ---------- 01 变量 ---------- */
:root{
  --ink-900:#071426;
  --ink-800:#0D1F38;
  --ink-700:#0F2A4A;
  --pulse:#3BE7D2;
  --flare:#FF7A2F;
  --moss:#8FA89B;
  --paper:#F2F6FA;
  --dim:#7C8DA3;
  --shade:#0B3B3C;
  --amber:#F4C542;

  --line:rgba(143,168,155,.20);
  --line-strong:rgba(143,168,155,.42);
  --grid-fine:rgba(143,168,155,.075);
  --soft:rgba(242,246,250,.78);
  --softer:rgba(242,246,250,.60);

  --font-sans:"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Source Han Sans SC","Noto Sans SC",system-ui,-apple-system,"Segoe UI",Arial,sans-serif;
  --font-mono:ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,"Liberation Mono",monospace;

  --w-max:1280px;
  --pad-x:clamp(16px,4vw,52px);
  --gap:clamp(16px,2vw,24px);
  --space-block:clamp(56px,7vw,104px);
  --rail-w:76px;
  --header-h:108px;
  --ease:cubic-bezier(.22,.61,.36,1);
  --radius:2px;
}

/* ---------- 02 重置与基础排版 ---------- */
*,*::before,*::after{box-sizing:border-box;}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:calc(var(--header-h) + 16px);}
body{
  margin:0;
  background:var(--ink-900);
  color:var(--paper);
  font-family:var(--font-sans);
  font-size:16.5px;
  line-height:1.75;
  overflow-x:hidden;
  -webkit-font-smoothing:antialiased;
}
body::before{
  content:"";
  position:fixed;inset:0;z-index:0;pointer-events:none;
  background-image:
    linear-gradient(to right,var(--grid-fine) 1px,transparent 1px),
    linear-gradient(to bottom,var(--grid-fine) 1px,transparent 1px);
  background-size:88px 88px;
  opacity:.7;
}
body::after{
  content:"";
  position:fixed;inset:0;z-index:0;pointer-events:none;
  background-image:radial-gradient(rgba(242,246,250,.035) 1px,transparent 1px);
  background-size:3px 3px;
  opacity:.6;
}
img,svg,video{max-width:100%;}
h1,h2,h3,h4,p,figure,ul,ol{margin:0;}
ul,ol{padding:0;list-style:none;}
a{color:var(--pulse);text-decoration:none;}
a:hover{color:var(--paper);}
button{font:inherit;color:inherit;}
::selection{background:rgba(59,231,210,.28);color:#fff;}
hr{border:0;height:1px;background:var(--line);margin:0;}

.yb-skip{
  position:fixed;left:16px;top:-90px;z-index:400;
  padding:10px 20px;background:var(--pulse);color:#04121f;
  font-weight:600;font-size:14px;letter-spacing:.06em;
  border-radius:var(--radius);transition:top .18s var(--ease);
}
.yb-skip:focus{top:14px;color:#04121f;}

#main-content{position:relative;z-index:1;padding-top:var(--header-h);}

.yb-hero{
  position:relative;
  margin-top:calc(var(--header-h) * -1);
  padding-top:calc(var(--header-h) + clamp(36px,6vw,84px));
  padding-bottom:clamp(44px,6vw,88px);
  overflow:hidden;
}

/* ---------- 03 布局容器与网格 ---------- */
.yb-container{
  width:100%;max-width:var(--w-max);
  margin-inline:auto;padding-inline:var(--pad-x);
}
.yb-section{position:relative;padding-block:var(--space-block);}
.yb-section--panel{background:var(--ink-800);}
.yb-section--tight{padding-block:clamp(32px,4vw,56px);}

.yb-grid{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));gap:var(--gap);}
.yb-grid--split{display:grid;grid-template-columns:minmax(0,1fr);gap:clamp(24px,3vw,48px);}
.yb-grid--read{display:grid;grid-template-columns:minmax(0,1fr);gap:clamp(24px,3vw,48px);}
@media (min-width:900px){
  .yb-grid--split{grid-template-columns:7fr 5fr;}
  .yb-grid--read{grid-template-columns:8fr 4fr;align-items:start;}
}

.yb-rail{display:grid;grid-template-columns:var(--rail-w) minmax(0,1fr);gap:0 clamp(12px,2vw,28px);position:relative;}
.yb-rail__track{border-right:1px solid var(--line);padding-right:12px;text-align:right;}
.yb-rail__num{display:block;font-family:var(--font-mono);font-size:11px;letter-spacing:.16em;color:var(--pulse);font-variant-numeric:tabular-nums;}
.yb-rail__label{display:block;font-family:var(--font-mono);font-size:10px;letter-spacing:.18em;color:var(--dim);text-transform:uppercase;writing-mode:vertical-rl;margin:10px 0 0 auto;}

/* ---------- 04 通用组件 ---------- */
.yb-eyebrow{
  font-family:var(--font-mono);font-size:12px;letter-spacing:.2em;
  text-transform:uppercase;color:var(--pulse);margin-bottom:14px;
}
.yb-h1{
  font-size:clamp(40px,6.4vw,96px);
  font-weight:300;line-height:1.02;letter-spacing:.04em;margin:0;
}
.yb-h1 b,.yb-h1 strong{font-weight:600;color:var(--paper);}
.yb-h2{
  font-size:clamp(26px,3.4vw,44px);
  font-weight:300;line-height:1.16;letter-spacing:.04em;margin:0 0 18px;
}
.yb-h2 b,.yb-h2 strong{font-weight:600;}
.yb-h3{
  font-size:clamp(18px,2vw,22px);
  font-weight:600;line-height:1.4;letter-spacing:.03em;margin:0 0 10px;
}
.yb-lede{
  font-size:clamp(16px,1.6vw,18px);line-height:1.8;
  color:var(--soft);max-width:46ch;
}
.yb-prose{color:var(--soft);font-size:16.5px;line-height:1.78;}
.yb-prose p{max-width:68ch;margin-bottom:1.1em;}
.yb-prose p:last-child{margin-bottom:0;}
.yb-prose h3{margin-top:2em;color:var(--paper);}
.yb-prose ul{display:grid;gap:10px;margin-bottom:1.2em;max-width:68ch;}
.yb-prose li{position:relative;padding-left:20px;}
.yb-prose li::before{content:"";position:absolute;left:0;top:.72em;width:8px;height:1px;background:var(--pulse);}
.yb-mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums;letter-spacing:.08em;}

.yb-tag{
  display:inline-flex;align-items:center;gap:8px;
  padding:4px 10px;border:1px solid var(--line-strong);border-radius:var(--radius);
  font-family:var(--font-mono);font-size:11px;letter-spacing:.14em;
  text-transform:uppercase;color:var(--moss);
}
.yb-tag--pulse{color:var(--pulse);border-color:rgba(59,231,210,.45);background:rgba(59,231,210,.07);}
.yb-tag--flare{color:var(--flare);border-color:rgba(255,122,47,.45);background:rgba(255,122,47,.08);}

.yb-btn{
  display:inline-flex;align-items:center;justify-content:center;gap:10px;
  padding:14px 24px;border:1px solid var(--line-strong);border-radius:var(--radius);
  background:transparent;color:var(--paper);
  font-size:15px;font-weight:600;letter-spacing:.06em;
  cursor:pointer;transition:background .18s var(--ease),color .18s var(--ease),border-color .18s var(--ease),box-shadow .2s var(--ease);
}
.yb-btn:hover{background:rgba(242,246,250,.06);color:var(--paper);border-color:var(--pulse);}
.yb-btn--primary{background:var(--pulse);border-color:var(--pulse);color:#04121f;}
.yb-btn--primary:hover{background:#2ad6c2;border-color:#2ad6c2;color:#04121f;box-shadow:0 0 0 4px rgba(59,231,210,.14);}
.yb-btn--flare{background:var(--flare);border-color:var(--flare);color:#1a0b00;}
.yb-btn--flare:hover{background:#ff8c4c;border-color:#ff8c4c;color:#1a0b00;box-shadow:0 0 0 4px rgba(255,122,47,.16);}
.yb-btn--ghost{background:transparent;border-color:rgba(59,231,210,.4);color:var(--pulse);}
.yb-btn--ghost:hover{background:rgba(59,231,210,.1);color:var(--pulse);}

.yb-panel{
  position:relative;background:var(--ink-800);border-radius:var(--radius);
  padding:clamp(18px,2.4vw,30px);
}
.yb-panel--edge::before{
  content:"";position:absolute;left:0;top:0;height:1px;width:100%;
  background:linear-gradient(90deg,var(--pulse),rgba(59,231,210,0) 62%);
}

.yb-crumbs{margin-bottom:clamp(18px,2.4vw,28px);}
.yb-crumbs__list{display:flex;flex-wrap:wrap;gap:8px;font-family:var(--font-mono);font-size:11.5px;letter-spacing:.12em;color:var(--dim);}
.yb-crumbs__item{display:flex;align-items:center;gap:8px;}
.yb-crumbs__item + .yb-crumbs__item::before{content:"/";color:var(--line-strong);}
.yb-crumbs__link{color:var(--dim);transition:color .16s var(--ease);}
.yb-crumbs__link:hover{color:var(--pulse);}
.yb-crumbs__current{color:var(--paper);}

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

/* ---------- 05 图片容器 ---------- */
.yb-media{
  position:relative;display:block;overflow:hidden;isolation:isolate;
  background:var(--ink-800);border-radius:var(--radius);
}
.yb-media img,.yb-media svg,.yb-media video{
  display:block;width:100%;height:100%;object-fit:cover;
}
.yb-media::after{
  content:"";position:absolute;inset:0;pointer-events:none;z-index:1;
  background:linear-gradient(180deg,rgba(11,59,60,.10) 0%,rgba(7,20,38,.32) 55%,rgba(7,20,38,.86) 100%);
}
.yb-media--wide{aspect-ratio:16/9;}
.yb-media--band{aspect-ratio:21/9;}
.yb-media--tall{aspect-ratio:3/4;}
.yb-media--square{aspect-ratio:1/1;}
.yb-media--grid::before{
  content:"";position:absolute;inset:0;z-index:2;pointer-events:none;opacity:.5;
  background-image:
    linear-gradient(to right,rgba(59,231,210,.16) 1px,transparent 1px),
    linear-gradient(to bottom,rgba(59,231,210,.16) 1px,transparent 1px);
  background-size:48px 48px;mix-blend-mode:screen;
}
.yb-media__cap{
  position:absolute;left:0;right:0;bottom:0;z-index:3;
  padding:14px 16px;font-family:var(--font-mono);
  font-size:11px;letter-spacing:.12em;color:rgba(242,246,250,.86);
}

/* ---------- 06 头部 ---------- */
.yb-header{
  position:fixed;top:0;left:0;right:0;z-index:200;
  color:var(--paper);background:transparent;
  transition:background .24s var(--ease),box-shadow .24s var(--ease);
}
.yb-header::after{
  content:"";position:absolute;left:0;right:0;bottom:0;height:1px;z-index:1;
  background:linear-gradient(90deg,rgba(143,168,155,0) 0%,var(--line-strong) 18%,var(--line-strong) 82%,rgba(143,168,155,0) 100%);
}
.yb-header[data-scrolled]{
  background:rgba(8,23,43,.95);
  box-shadow:0 22px 44px -34px #000;
}

.yb-header__progress{
  position:absolute;left:0;bottom:0;height:2px;width:100%;z-index:3;
  background:linear-gradient(90deg,var(--pulse),var(--flare));
  transform:scaleX(var(--yb-progress,0));transform-origin:left center;
  transition:transform .12s linear;
}

.yb-header__strip{
  height:34px;display:flex;align-items:center;
  background:rgba(7,20,38,.62);
  border-bottom:1px solid var(--line);
  overflow:hidden;
  transition:height .24s var(--ease),opacity .2s var(--ease),visibility .24s;
}
.yb-header__stripinner{
  width:100%;max-width:var(--w-max);margin-inline:auto;padding-inline:var(--pad-x);
  display:flex;align-items:center;gap:clamp(12px,3vw,40px);
  font-family:var(--font-mono);font-size:11.5px;letter-spacing:.14em;
  color:var(--dim);text-transform:uppercase;
}
.yb-strip__item{display:flex;align-items:center;gap:8px;white-space:nowrap;margin:0;}
.yb-strip__item--lead{color:var(--moss);}
.yb-strip__item:last-child{margin-left:auto;}
.yb-strip__dot{
  width:6px;height:6px;border-radius:50%;background:var(--pulse);
  box-shadow:0 0 0 3px rgba(59,231,210,.16);
  animation:yb-pulse 2.6s var(--ease) infinite;
}
@keyframes yb-pulse{
  0%,100%{opacity:1;box-shadow:0 0 0 3px rgba(59,231,210,.16);}
  50%{opacity:.55;box-shadow:0 0 0 6px rgba(59,231,210,.04);}
}

.yb-header__barinner{
  width:100%;max-width:var(--w-max);margin-inline:auto;padding-inline:var(--pad-x);
  display:flex;align-items:center;gap:clamp(14px,2.4vw,36px);
  height:74px;
  transition:height .24s var(--ease);
}
.yb-header[data-scrolled] .yb-header__barinner{height:62px;}
.yb-header[data-scrolled] .yb-header__strip{
  height:0;opacity:0;visibility:hidden;border-bottom-color:transparent;
}

.yb-brand{display:inline-flex;align-items:center;gap:12px;flex:0 0 auto;color:var(--paper);}
.yb-brand:hover{color:var(--paper);}
.yb-brand__mark{
  position:relative;width:34px;height:34px;flex:0 0 auto;
  border:1px solid rgba(59,231,210,.5);
}
.yb-brand__mark span{position:absolute;width:10px;height:10px;}
.yb-brand__mark span:first-child{top:6px;left:6px;background:var(--pulse);}
.yb-brand__mark span:last-child{bottom:6px;right:6px;background:var(--flare);}
.yb-brand__type{display:block;}
.yb-brand__name{display:block;font-size:19px;font-weight:600;letter-spacing:.16em;line-height:1.2;}
.yb-brand__tag{
  display:block;margin-top:4px;white-space:nowrap;
  font-family:var(--font-mono);font-size:10.5px;letter-spacing:.12em;color:var(--dim);
}

.yb-nav{margin-left:auto;}
.yb-nav__list{display:flex;align-items:center;gap:clamp(8px,1.5vw,24px);counter-reset:navi;}
.yb-nav__link{
  position:relative;display:inline-flex;align-items:baseline;gap:6px;
  padding:8px 2px;color:rgba(242,246,250,.82);
  font-size:14.5px;letter-spacing:.06em;white-space:nowrap;
  transition:color .18s var(--ease);
}
.yb-nav__link::before{
  counter-increment:navi;content:"0" counter(navi);
  font-family:var(--font-mono);font-size:10px;letter-spacing:.08em;
  color:var(--dim);transition:color .18s var(--ease);
}
.yb-nav__link::after{
  content:"";position:absolute;left:0;right:0;bottom:0;height:1px;
  background:var(--pulse);transform:scaleX(0);transform-origin:left center;
  transition:transform .18s var(--ease);
}
.yb-nav__link:hover{color:var(--paper);}
.yb-nav__link:hover::after{transform:scaleX(1);}
.yb-nav__link[aria-current="page"]{color:var(--pulse);}
.yb-nav__link[aria-current="page"]::before{color:var(--pulse);}
.yb-nav__link[aria-current="page"]::after{transform:scaleX(1);}
.yb-nav__foot{display:none;}

.yb-header__tools{display:flex;align-items:center;gap:12px;flex:0 0 auto;}

.yb-hop{
  position:relative;display:inline-flex;align-items:center;gap:10px;
  padding:9px 14px 9px 10px;border-radius:var(--radius);
  border:1px solid rgba(255,122,47,.55);
  background:rgba(255,122,47,.08);color:var(--paper);
  transition:background .18s var(--ease),border-color .18s var(--ease),box-shadow .2s var(--ease);
}
.yb-hop:hover{background:rgba(255,122,47,.18);border-color:var(--flare);color:var(--paper);box-shadow:0 0 0 4px rgba(255,122,47,.12);}
.yb-hop__boxes{display:inline-flex;align-items:center;}
.yb-hop__box{
  width:20px;height:20px;display:grid;place-items:center;
  font-family:var(--font-mono);font-size:10px;line-height:1;
  background:var(--flare);color:#1a0b00;
}
.yb-hop__box:last-child{
  margin-left:-5px;background:transparent;color:var(--flare);
  border:1px solid rgba(255,122,47,.7);
}
.yb-hop__label{font-size:14px;font-weight:600;letter-spacing:.06em;}
.yb-hop__note{
  position:absolute;left:0;top:calc(100% + 6px);
  font-family:var(--font-mono);font-size:10.5px;letter-spacing:.1em;
  color:var(--flare);white-space:nowrap;pointer-events:none;
  opacity:0;transform:translateY(-4px);
  transition:opacity .18s var(--ease),transform .18s var(--ease);
}
.yb-hop:hover .yb-hop__note,.yb-hop:focus-visible .yb-hop__note{opacity:1;transform:none;}

.yb-burger{
  display:none;align-items:center;gap:8px;
  padding:8px 12px;border-radius:var(--radius);
  border:1px solid var(--line-strong);background:transparent;color:var(--paper);
  font-family:var(--font-mono);font-size:11px;letter-spacing:.16em;text-transform:uppercase;
  cursor:pointer;transition:border-color .18s var(--ease),color .18s var(--ease);
}
.yb-burger:hover{border-color:var(--pulse);color:var(--pulse);}
.yb-burger__bars{
  display:inline-flex;flex-direction:column;justify-content:center;gap:5px;
  width:16px;height:12px;
}
.yb-burger__bars span{display:block;height:1.5px;background:currentColor;transition:transform .2s var(--ease);}
.yb-burger[aria-expanded="true"] .yb-burger__bars span:first-child{transform:translateY(3.25px) rotate(45deg);}
.yb-burger[aria-expanded="true"] .yb-burger__bars span:last-child{transform:translateY(-3.25px) rotate(-45deg);}

/* ---------- 07 页脚 ---------- */
.yb-footer{
  position:relative;z-index:1;
  background:var(--ink-800);
  border-top:1px solid var(--line-strong);
  overflow:hidden;
}
.yb-footer::before{
  content:"";position:absolute;left:0;top:0;height:1px;width:100%;
  background:linear-gradient(90deg,var(--pulse),rgba(59,231,210,0) 46%,rgba(255,122,47,0) 62%,var(--flare));
  opacity:.7;
}
.yb-footer::after{
  content:"";position:absolute;inset:0;pointer-events:none;
  background-image:
    linear-gradient(to right,rgba(143,168,155,.06) 1px,transparent 1px),
    linear-gradient(to bottom,rgba(143,168,155,.06) 1px,transparent 1px);
  background-size:88px 88px;
}
.yb-footer > *{position:relative;z-index:1;}

.yb-footer__inner{
  display:grid;grid-template-columns:minmax(0,1fr);gap:clamp(28px,4vw,64px);
  padding-block:clamp(40px,5vw,72px) clamp(28px,3.4vw,48px);
}
.yb-footer__eyebrow{
  font-family:var(--font-mono);font-size:11px;letter-spacing:.2em;
  text-transform:uppercase;color:var(--pulse);margin-bottom:14px;
}
.yb-footer__brand{
  font-size:clamp(20px,2.4vw,28px);font-weight:300;
  letter-spacing:.06em;line-height:1.32;margin-bottom:14px;
}
.yb-footer__note{font-size:13.5px;line-height:1.8;color:var(--dim);max-width:38ch;}

.yb-footer__cols{
  display:grid;grid-template-columns:repeat(auto-fit,minmax(148px,1fr));
  gap:clamp(20px,3vw,40px);align-content:start;
}
.yb-footer__title{
  font-family:var(--font-mono);font-size:11px;font-weight:500;
  letter-spacing:.2em;text-transform:uppercase;color:var(--moss);
  margin-bottom:14px;
}
.yb-footer__list{display:grid;gap:10px;}
.yb-footer__link{
  position:relative;display:inline-block;color:rgba(242,246,250,.8);
  font-size:14.5px;letter-spacing:.02em;
  transition:color .16s var(--ease),transform .16s var(--ease);
}
.yb-footer__link:hover{color:var(--pulse);transform:translateX(3px);}
.yb-footer__contact{font-style:normal;display:grid;gap:10px;font-size:13.5px;color:rgba(242,246,250,.78);line-height:1.7;}
.yb-footer__contact p{display:grid;grid-template-columns:auto minmax(0,1fr);gap:10px;;}
.yb-footer__ck{
  font-family:var(--font-mono);font-size:10.5px;letter-spacing:.14em;
  color:var(--dim);padding-top:3px;white-space:nowrap;
}

.yb-footer__bottom{
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;
  gap:14px;padding-block:18px 26px;border-top:1px solid var(--line);
}
.yb-footer__legal{font-size:12.5px;color:var(--dim);letter-spacing:.04em;}
.yb-footer__meta{font-size:12.5px;color:var(--dim);letter-spacing:.04em;}
.yb-footer__version{display:flex;align-items:center;gap:12px;flex-wrap:wrap;}

.yb-version{
  display:inline-flex;align-items:center;gap:10px;
  padding:7px 12px;border-radius:var(--radius);
  border:1px solid rgba(59,231,210,.35);background:rgba(59,231,210,.06);
  color:var(--paper);cursor:pointer;
  transition:background .18s var(--ease),border-color .18s var(--ease);
}
.yb-version:hover{background:rgba(59,231,210,.14);border-color:var(--pulse);}
.yb-version__key{font-family:var(--font-mono);font-size:10px;letter-spacing:.16em;color:var(--moss);}
.yb-version__val{
  font-family:var(--font-mono);font-variant-numeric:tabular-nums;
  font-size:12.5px;letter-spacing:.08em;color:var(--pulse);
}
.yb-version__cue{
  font-family:var(--font-mono);font-size:10px;letter-spacing:.14em;
  color:var(--dim);border-left:1px solid var(--line);padding-left:10px;
  transition:color .18s var(--ease);
}
.yb-version[data-copied] .yb-version__cue{color:var(--flare);}
.yb-version__state{
  font-family:var(--font-mono);font-size:11px;letter-spacing:.1em;
  color:var(--pulse);min-height:1em;
}

/* ---------- 08 响应式 ---------- */
@media (min-width:860px){
  .yb-footer__inner{grid-template-columns:minmax(0,5fr) minmax(0,7fr);}
}
@media (max-width:1199px){
  .yb-brand__tag{display:none;}
  .yb-nav__list{gap:clamp(6px,1.1vw,16px);}
  .yb-nav__link{font-size:13.5px;}
}
@media (max-width:1080px){
  .yb-brand__name{font-size:17.5px;letter-spacing:.12em;}
  .yb-header__barinner{gap:14px;}
}
@media (max-width:980px){
  :root{--header-h:62px;--rail-w:0px;}
  .yb-header__strip{display:none;}
  .yb-header__barinner{height:62px;}
  .yb-header[data-scrolled] .yb-header__barinner{height:58px;}
  .yb-brand__name{font-size:17px;}
  .yb-brand__mark{width:30px;height:30px;}
  .yb-brand__mark span{width:9px;height:9px;}
  .yb-brand__mark span:first-child{top:5px;left:5px;}
  .yb-brand__mark span:last-child{bottom:5px;right:5px;}
  .yb-hop{display:none;}
  .yb-burger{display:inline-flex;}

  .yb-nav{
    position:fixed;left:0;right:0;top:var(--header-h);
    margin-left:0;
    max-height:calc(100vh - var(--header-h));
    overflow-y:auto;
    padding:10px var(--pad-x) 28px;
    background:rgba(8,23,43,.985);
    border-top:1px solid var(--line);
    box-shadow:0 30px 60px -30px #000;
    opacity:0;visibility:hidden;pointer-events:none;
    transform:translateY(-10px);
    transition:opacity .2s var(--ease),transform .2s var(--ease),visibility .2s;
  }
  .yb-header[data-open] .yb-nav{
    opacity:1;visibility:visible;pointer-events:auto;transform:none;
  }
  .yb-nav__list{flex-direction:column;align-items:stretch;gap:0;}
  .yb-nav__item{border-bottom:1px solid var(--line);}
  .yb-nav__link{
    width:100%;justify-content:flex-start;gap:12px;
    padding:16px 2px;font-size:17px;letter-spacing:.08em;
  }
  .yb-nav__link::after{display:none;}
  .yb-nav__link[aria-current="page"]{color:var(--pulse);}
  .yb-nav__foot{
    display:block;margin-top:20px;
    font-family:var(--font-mono);font-size:11px;letter-spacing:.12em;
    color:var(--dim);line-height:1.9;
  }
}
@media (max-width:760px){
  .yb-rail{grid-template-columns:minmax(0,1fr);}
  .yb-rail__track{display:none;}
  .yb-footer__contact p{grid-template-columns:minmax(0,1fr);gap:2px;}
  .yb-footer__bottom{flex-direction:column;align-items:flex-start;}
  .yb-section{padding-block:clamp(40px,9vw,64px);}
  .yb-lede{max-width:100%;}
}
@media (max-width:420px){
  .yb-burger__text{display:none;}
  .yb-version__key{display:none;}
  .yb-version__cue{display:none;}
}

/* ---------- 09 可访问性与动效降级 ---------- */
:focus-visible{
  outline:2px solid var(--pulse);
  outline-offset:3px;
  border-radius:2px;
}
.yb-version:focus-visible,
.yb-burger:focus-visible,
.yb-hop:focus-visible{outline-offset:2px;}

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