@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

:root{
  --ink:#0E0E10;
  --paper:#EDE9E3;
  --hot:#FF4D6D;
  --deep:#C42B4C;
  --line-d:rgba(237,233,227,.18);
  --line-l:rgba(14,14,16,.16);
}
*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%;max-width:100%}
body{
  margin:0;
  max-width:100%;
  background:var(--ink);
  color:var(--paper);
  font-family:Inter,"PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  font-size:17px;
  line-height:1.6;
  overflow-x:hidden;
}
a{color:inherit}
img{max-width:100%}
h1,h2,h3{margin:0}
p{margin:0}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}
.skip{position:fixed;left:8px;top:-70px;z-index:200;background:var(--hot);color:var(--ink);padding:12px 18px;text-decoration:none;font-weight:600}
.skip:focus{top:8px}

/* ---------- 固定左栏 ---------- */
.shell{display:block;max-width:100%;overflow-x:clip}
.rail{
  position:fixed;
  left:0;top:0;bottom:0;
  width:112px;
  display:flex;
  flex-direction:column;
  align-items:stretch;
  padding:18px 0 16px;
  background:var(--ink);
  border-right:1px solid var(--line-d);
  z-index:60;
}
.mark{
  margin:0 auto;
  width:46px;height:46px;
  display:flex;align-items:center;justify-content:center;
  border:1px solid var(--hot);
  color:var(--hot);
  text-decoration:none;
  font-size:20px;font-weight:700;
  letter-spacing:0;
  transition:background .25s,color .25s;
}
.mark:hover,.mark:focus-visible{background:var(--hot);color:var(--ink)}
.rail-links{
  display:flex;
  flex-direction:column;
  margin-top:26px;
  flex:1 1 auto;
  min-width:0;
  overflow-y:auto;
  overflow-x:hidden;
}
.rail-link{
  display:block;
  padding:18px 4px;
  min-height:44px;
  text-align:center;
  text-decoration:none;
  font-size:16px;
  letter-spacing:.18em;
  writing-mode:vertical-rl;
  text-orientation:upright;
  border-bottom:1px solid var(--line-d);
  transition:color .2s,background .2s;
}
.rail-link:hover,.rail-link:focus-visible{color:var(--hot);background:rgba(255,77,109,.08)}
.rail-search{
  display:flex;
  flex-direction:column;
  gap:6px;
  padding:12px 10px 0;
  min-width:0;
  border-top:1px solid var(--line-d);
}
.rail-search input{
  width:100%;
  min-width:0;
  min-height:42px;
  background:transparent;
  border:1px solid rgba(237,233,227,.32);
  border-radius:0;
  color:var(--paper);
  font:inherit;
  font-size:16px;
  padding:6px 8px;
}
.rail-search input::placeholder{color:rgba(237,233,227,.55)}
.rail-search input:focus{outline:2px solid var(--hot);outline-offset:1px}
.rail-search button{
  min-height:42px;
  border:0;border-radius:0;
  background:var(--hot);
  color:var(--ink);
  font:inherit;
  font-size:16px;
  font-weight:700;
  letter-spacing:.2em;
  cursor:pointer;
}
.rail-search button:hover{background:var(--paper)}

.stage{margin-left:112px;background:var(--paper);color:var(--ink);min-height:100vh;min-width:0}

/* ---------- 首屏 ---------- */
.hero{
  position:relative;
  min-height:100vh;
  min-height:100svh;
  display:flex;
  flex-direction:column;
  justify-content:space-between;
  gap:26px;
  padding:42px clamp(24px,5vw,74px) 0;
  background:var(--ink);
  color:var(--paper);
  overflow:hidden;
  border-bottom:1px solid var(--line-d);
}
.hero-head{
  display:flex;
  flex-direction:column;
  align-items:flex-end;
  gap:18px;
  text-align:right;
  min-width:0;
}
.badge{
  border:1px solid var(--hot);
  color:var(--hot);
  padding:6px 14px;
  font-size:16px;
  letter-spacing:.22em;
  animation:float 6s ease-in-out infinite;
}
@keyframes float{
  0%,100%{transform:translate3d(0,0,0)}
  50%{transform:translate3d(0,-7px,0)}
}
.hero h1{
  max-width:22ch;
  font-size:clamp(2.35rem,8.4vw,7.4rem);
  line-height:.96;
  letter-spacing:-.035em;
  font-weight:700;
  overflow-wrap:break-word;
  background:linear-gradient(98deg,var(--hot) 6%,#FFFFFF 48%,var(--paper) 92%);
  -webkit-background-clip:text;
  background-clip:text;
  color:transparent;
  -webkit-text-fill-color:transparent;
}
.hero h1 .ch{
  display:inline-block;
  opacity:0;
  transform:translateY(.55em) rotate(5deg);
  transition:opacity .5s ease,transform .7s cubic-bezier(.18,.82,.2,1);
}
.hero h1.go .ch{opacity:1;transform:none}
.hero-desc{
  max-width:46ch;
  font-size:1.0625rem;
  line-height:1.6;
  color:rgba(237,233,227,.72);
  overflow-wrap:break-word;
}
.hero-fig{
  margin:0;
  position:relative;
  height:44vh;
  min-height:190px;
  display:flex;
  align-items:flex-end;
  justify-content:flex-end;
  overflow:hidden;
  border-top:1px solid var(--line-d);
  will-change:transform;
}
.hero-img{width:100%;height:100%;object-fit:cover;display:block}
.hero-word{
  font-size:clamp(3rem,13vw,10rem);
  line-height:.82;
  font-weight:700;
  letter-spacing:-.045em;
  color:transparent;
  -webkit-text-stroke:1px var(--hot);
  white-space:nowrap;
  transform:translateY(10%);
}
.ticker{
  overflow:hidden;
  border-top:1px solid var(--line-d);
  padding:11px 0;
}
.ticker-track{
  display:flex;
  width:max-content;
  animation:slide 30s linear infinite;
}
.ticker-track span{
  font-size:16px;
  letter-spacing:.26em;
  color:var(--hot);
  padding:0 16px;
  white-space:nowrap;
}
@keyframes slide{
  from{transform:translateX(0)}
  to{transform:translateX(-50%)}
}

/* ---------- 正文 + 侧栏 ---------- */
.body{
  display:grid;
  grid-template-columns:250px minmax(0,1fr);
  background:var(--paper);
  color:var(--ink);
  min-width:0;
}
.toc{
  border-right:1px solid var(--line-l);
  padding:34px 22px;
  position:sticky;
  top:0;
  align-self:start;
  max-height:100vh;
  overflow:auto;
  min-width:0;
}
.toc h2{
  font-size:16px;
  letter-spacing:.26em;
  font-weight:600;
  margin-bottom:16px;
}
.toc h2 span{display:inline-block;border-bottom:3px solid var(--hot);padding-bottom:5px}
.toc ol{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;min-width:0}
.toc li a{
  display:block;
  padding:11px 0;
  min-height:40px;
  font-size:16px;
  text-decoration:none;
  border-bottom:1px solid rgba(14,14,16,.12);
  transition:padding-left .2s,color .2s;
}
.toc li a:hover,.toc li a:focus-visible{color:var(--deep);padding-left:6px}

.doc{
  padding:36px clamp(22px,4vw,58px) 80px;
  min-width:0;
  max-width:840px;
  overflow-wrap:break-word;
}
.doc > section{
  padding:40px 0 48px;
  border-bottom:1px solid var(--line-l);
  scroll-margin-top:16px;
}
.js .doc > section{
  opacity:0;
  transform:translateY(26px);
  transition:opacity .6s ease,transform .7s cubic-bezier(.18,.82,.2,1);
}
.js .doc > section.in{opacity:1;transform:none}
.doc h2{
  font-size:clamp(1.5rem,3vw,2.15rem);
  line-height:1.16;
  letter-spacing:-.02em;
  margin-bottom:16px;
}
.doc h2 span{display:inline-block;position:relative;padding-bottom:10px}
.doc h2 span::after{
  content:"";
  position:absolute;left:0;bottom:0;
  width:52px;height:4px;background:var(--hot);
}
.doc h3{
  font-size:1.25rem;
  line-height:1.35;
  margin:26px 0 10px;
  letter-spacing:-.01em;
}
.doc p,.doc li{font-size:1.0625rem;line-height:1.75}
.doc p{margin:0 0 16px}
.doc ul,.doc ol{margin:0 0 18px;padding-left:1.35em}
.doc li{margin-bottom:8px}
.doc a{color:var(--deep);text-decoration:underline;text-underline-offset:3px}
.doc a:hover{background:rgba(255,77,109,.16)}
.doc strong{font-weight:700}
.doc blockquote{
  margin:22px 0;
  padding:14px 20px;
  border-left:4px solid var(--hot);
  background:rgba(255,77,109,.07);
}
.doc blockquote p:last-child{margin-bottom:0}
.doc figure{margin:22px 0}
.doc figcaption{font-size:16px;color:rgba(14,14,16,.62);margin-top:8px}
.doc img{max-width:100%;height:auto;display:block;border-radius:0}
.doc pre{max-width:100%;overflow-x:auto;padding:14px 16px;background:rgba(14,14,16,.06);font-size:16px;line-height:1.55}
.doc table{width:100%;border-collapse:collapse;margin:20px 0;font-size:16px}
.doc th,.doc td{border:1px solid rgba(14,14,16,.2);padding:9px 11px;text-align:left;line-height:1.6}
.doc th{background:rgba(14,14,16,.06);font-weight:600}
.doc > section:last-child{border-bottom:0}

/* ---------- 页脚 ---------- */
.foot{
  background:var(--ink);
  color:var(--paper);
  padding:48px clamp(22px,4vw,58px) 26px;
  border-top:1px solid var(--line-d);
}
.foot-form{
  display:grid;
  gap:14px;
  max-width:520px;
  padding-bottom:34px;
  margin-bottom:36px;
  border-bottom:1px solid var(--line-d);
}
.foot-form h2{font-size:16px;letter-spacing:.26em;font-weight:600}
.foot-form h2 span{display:inline-block;border-bottom:3px solid var(--hot);padding-bottom:5px}
.sub-form{display:flex;gap:8px}
.sub-form input{
  flex:1 1 auto;
  min-width:0;
  min-height:46px;
  background:transparent;
  border:1px solid rgba(237,233,227,.34);
  border-radius:0;
  color:var(--paper);
  font:inherit;
  font-size:16px;
  padding:8px 10px;
}
.sub-form input::placeholder{color:rgba(237,233,227,.55)}
.sub-form input:focus{outline:2px solid var(--hot);outline-offset:1px}
.sub-form button{
  min-height:46px;
  padding:0 22px;
  border:0;border-radius:0;
  background:var(--hot);
  color:var(--ink);
  font:inherit;
  font-size:16px;
  font-weight:700;
  letter-spacing:.16em;
  cursor:pointer;
}
.sub-form button:hover{background:var(--paper)}
.foot-grid{
  display:grid;
  grid-template-columns:repeat(3,minmax(0,1fr));
  gap:26px;
  padding-bottom:34px;
  border-bottom:1px solid var(--line-d);
}
.foot-grid dl{margin:0;display:flex;flex-direction:column;gap:2px;min-width:0}
.foot-grid dt{
  font-size:16px;
  letter-spacing:.24em;
  color:var(--hot);
  margin-bottom:8px;
}
.foot-grid dd{
  margin:0;
  font-size:16px;
  color:rgba(237,233,227,.8);
  overflow-wrap:anywhere;
}
.foot-grid dd a{
  display:inline-block;
  padding:9px 0;
  min-height:40px;
  text-decoration:none;
  border-bottom:1px solid transparent;
  transition:color .2s,border-color .2s;
}
.foot-grid dd a:hover,.foot-grid dd a:focus-visible{color:var(--hot);border-bottom-color:var(--hot)}
.foot-end{
  display:flex;
  justify-content:space-between;
  align-items:center;
  flex-wrap:wrap;
  gap:12px;
  padding-top:20px;
  font-size:16px;
  color:rgba(237,233,227,.7);
}
.foot-end a{
  display:inline-block;
  padding:10px 0;
  min-height:40px;
  text-decoration:none;
  border-bottom:1px solid var(--hot);
}
.foot-end a:hover{color:var(--hot)}

/* ---------- 移动端 ---------- */
@media (max-width:900px){
  .rail{
    position:sticky;
    top:0;bottom:auto;
    width:100%;
    max-width:100%;
    flex-wrap:wrap;
    flex-direction:row;
    align-items:center;
    gap:8px 10px;
    padding:8px 12px 0;
    border-right:0;
    border-bottom:1px solid var(--line-d);
  }
  .stage{margin-left:0;min-width:0}
  .mark{flex:0 0 auto;margin:0;width:44px;height:44px}
  .rail-search{
    flex:0 0 auto;
    flex-direction:row;
    align-items:center;
    margin-left:auto;
    padding:0;
    gap:6px;
    min-width:0;
    border-top:0;
  }
  .rail-search input{width:86px;min-height:44px}
  .rail-search button{min-height:44px;padding:0 12px;letter-spacing:.08em}
  .rail-links{
    order:3;
    flex:1 0 100%;
    min-width:0;
    flex-direction:row;
    align-items:center;
    gap:2px;
    margin-top:0;
    padding-bottom:7px;
    overflow-x:auto;
    overflow-y:hidden;
    scrollbar-width:none;
  }
  .rail-links::-webkit-scrollbar{display:none}
  .rail-link{
    writing-mode:horizontal-tb;
    display:flex;
    align-items:center;
    padding:12px 10px;
    min-height:44px;
    white-space:nowrap;
    border-bottom:0;
    letter-spacing:.08em;
  }
  .hero{
    min-height:auto;
    justify-content:flex-start;
    gap:26px;
    padding:26px 20px 0;
  }
  .hero-head{align-items:flex-start;text-align:left}
  .hero h1{max-width:none;font-size:clamp(2.1rem,10.4vw,3.4rem)}
  .hero-fig{height:32vh;min-height:150px}
  .hero-word{font-size:clamp(2.4rem,17vw,4.4rem)}
  .body{grid-template-columns:minmax(0,1fr)}
  .toc{
    position:static;
    max-height:none;
    overflow:visible;
    min-width:0;
    border-right:0;
    border-bottom:1px solid var(--line-l);
    padding:20px;
  }
  .toc h2{margin-bottom:12px}
  .toc ol{
    flex-direction:row;
    gap:8px;
    min-width:0;
    overflow-x:auto;
    overflow-y:hidden;
    padding-bottom:4px;
    scrollbar-width:none;
  }
  .toc ol::-webkit-scrollbar{display:none}
  .toc li a{
    white-space:nowrap;
    border-bottom:1px solid var(--line-l);
    padding:10px 13px;
    min-height:42px;
    display:flex;
    align-items:center;
  }
  .doc{padding:22px 20px 56px;max-width:none;min-width:0}
  .doc > section{padding:32px 0 36px}
  .doc table{display:block;max-width:100%;overflow-x:auto}
  .foot{padding:36px 20px 22px}
  .foot-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}
  .foot-grid dl:first-child{grid-column:1 / -1}
  .foot-end{font-size:16px}
}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .badge{animation:none}
  .ticker-track{animation:none}
  .hero h1 .ch{opacity:1;transform:none;transition:none}
  .js .doc > section{opacity:1;transform:none;transition:none}
  .hero-fig{transform:none!important}
}

button[aria-expanded]{min-width:44px;min-height:44px}