@import url('https://fonts.googleapis.com/css2?family=Space+Mono:wght@400;700&family=Syncopate:wght@400;700&display=swap');

*,*::before,*::after{box-sizing:border-box}

:root{
  --ink:#0B1020;
  --ink2:#0E1730;
  --cyan:#00E5FF;
  --amber:#FFB547;
  --txt:#DCE6F7;
  --dim:#93A5C4;
  --line:rgba(0,229,255,.20);
  --mono:"Space Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --wide:"Syncopate",var(--mono);
  --body:"Space Mono","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  --rail:216px;
}

html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  margin:0;
  background:var(--ink);
  color:var(--txt);
  font:400 17px/1.75 var(--body);
  letter-spacing:.01em;
  overflow-x:hidden;
}
img{display:block;max-width:100%}
a{color:var(--cyan);text-decoration:none}
h1,h2,h3{font-family:var(--wide);font-weight:700;line-height:1.28;letter-spacing:.02em;margin:0 0 .6em}
p{margin:0 0 1.1em}
menu,ol,ul{margin:0;padding:0;list-style:none}
:focus-visible{outline:2px solid var(--amber);outline-offset:2px}
[id]{scroll-margin-top:96px}

.skip{position:fixed;left:-9999px;top:8px;z-index:90;padding:10px 16px;border-radius:4px;background:#05090F;color:var(--cyan);border:1px solid var(--line)}
.skip:focus{left:8px}

/* ---- 视差背景层 ---- */
.bg{
  position:fixed;inset:0;z-index:-1;overflow:hidden;pointer-events:none;
  background:
    radial-gradient(60% 50% at 82% -6%,rgba(0,229,255,.14),transparent 70%),
    radial-gradient(50% 45% at 6% 92%,rgba(255,181,71,.10),transparent 72%),
    linear-gradient(180deg,#0B1020,#070C18 62%,#0B1020);
}
.bg span{position:absolute;left:-10%;right:-10%;top:-20%;height:140%;will-change:transform}
.bg .l1{background:repeating-linear-gradient(90deg,rgba(0,229,255,.06) 0 1px,transparent 1px 118px)}
.bg .l2{background:radial-gradient(40% 28% at 72% 18%,rgba(0,229,255,.11),transparent 70%)}
.bg .l3{background:radial-gradient(36% 26% at 18% 74%,rgba(255,181,71,.10),transparent 72%)}

/* ---- 左侧固定竖排导航 ---- */
.rail{
  position:fixed;left:0;top:0;bottom:0;width:var(--rail);z-index:40;
  display:flex;flex-direction:column;gap:14px;padding:18px 14px;
  background:rgba(8,13,26,.88);
  -webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);
  border-right:1px solid var(--line);
}
.brand{
  display:grid;place-items:center;width:44px;height:44px;flex:0 0 auto;
  border:1px solid var(--line);border-radius:4px;overflow:hidden;
  background:linear-gradient(150deg,rgba(0,229,255,.22),rgba(255,181,71,.14));
  color:#fff;font-family:var(--wide);font-size:15px;letter-spacing:.04em;
}
.brand:hover{border-color:var(--cyan);box-shadow:0 0 0 1px rgba(0,229,255,.35) inset}
.mark-img{width:100%;height:100%;object-fit:contain}

.menu-box{flex:1 1 auto;min-height:0;display:flex;flex-direction:column;margin-top:4px}
summary{
  list-style:none;cursor:pointer;display:flex;align-items:center;gap:9px;
  min-height:44px;padding:0 6px;font-family:var(--wide);font-size:13px;
  letter-spacing:.16em;color:var(--amber);border-bottom:1px solid var(--line);
}
summary::-webkit-details-marker{display:none}
summary .chev{width:8px;height:8px;border-right:1px solid currentColor;border-bottom:1px solid currentColor;transform:rotate(45deg);transition:transform .25s ease}
.menu-box:not([open]) .chev{transform:rotate(-45deg)}

.menu-box menu{margin-top:10px;display:flex;flex-direction:column;gap:2px;overflow-y:auto;min-height:0}
.menu-box a{
  display:flex;align-items:center;gap:10px;min-height:44px;padding:8px;
  color:var(--txt);font-size:16px;line-height:1.32;border-radius:4px;
  border-left:2px solid transparent;
}
.menu-box a:hover,.menu-box a:focus-visible{background:rgba(0,229,255,.10);border-left-color:var(--cyan);color:#fff}
.dot{flex:0 0 auto;width:6px;height:6px;border-radius:50%;background:var(--cyan);opacity:.7;transition:transform .2s ease,background .2s ease,opacity .2s ease}
.menu-box a:hover .dot{transform:scale(1.7);background:var(--amber);opacity:1}

/* ---- 英雄区 ---- */
.hero{
  position:relative;isolation:isolate;overflow:hidden;
  margin-left:var(--rail);min-height:45vh;display:grid;place-items:center;
  text-align:center;padding:56px 20px 60px;border-bottom:1px solid var(--line);
}
.hero-img{
  position:absolute;left:0;right:0;top:-8%;width:100%;height:116%;
  object-fit:cover;z-index:-3;opacity:.5;transform:scale(1.1);will-change:transform;
}
.hero::after{
  content:"";position:absolute;inset:0;z-index:-2;
  background:
    linear-gradient(180deg,rgba(11,16,32,.55),rgba(11,16,32,.94)),
    radial-gradient(62% 62% at 50% 42%,transparent,rgba(11,16,32,.85));
}
.bigword{
  position:absolute;left:50%;top:50%;transform:translate(-50%,-50%);
  z-index:-1;pointer-events:none;white-space:nowrap;
  font-family:var(--wide);font-weight:700;letter-spacing:.02em;
  font-size:clamp(56px,14vw,164px);
  color:rgba(0,229,255,.10);
  -webkit-text-stroke:1px rgba(0,229,255,.24);
}
.hero-inner{position:relative;max-width:820px}
.hero h1{font-size:clamp(26px,5.2vw,50px);color:#fff;margin:0 0 .55em;text-shadow:0 3px 34px rgba(0,0,0,.7)}
.hero-desc{margin:0;color:var(--dim);font-size:16px}

/* ---- 主体骨架：main > div.wrap > aside + section > article ---- */
main{margin-left:var(--rail);padding-bottom:64px}
.wrap{max-width:1120px;margin:0 auto;padding:40px 20px 0;display:grid;grid-template-columns:1fr;gap:26px}

.side{border-top:1px solid var(--line);padding-top:16px}
.side-h{margin:0 0 10px;font-size:14px;letter-spacing:.16em;color:var(--amber)}
.side-list{display:flex;flex-wrap:wrap;gap:4px 8px;counter-reset:s}
.side-list li{counter-increment:s}
.side-list a{
  display:inline-flex;align-items:center;gap:8px;min-height:40px;padding:4px 10px 4px 0;
  color:var(--dim);font-size:15px;line-height:1.4;border-radius:4px;
}
.side-list a::before{content:counter(s,decimal-leading-zero);font-family:var(--mono);font-size:11px;color:rgba(0,229,255,.66)}
.side-list a:hover{color:#fff}

.story{min-width:0}
.prose{font-size:17px}

.prose > section{
  padding:34px 0;border-top:1px solid rgba(0,229,255,.13);
  border-bottom:2px solid rgba(0,229,255,.10);border-radius:0 0 4px 4px;
}
.prose > section:first-child{border-top:0;padding-top:4px}
.prose h2{
  position:relative;padding-left:16px;margin:0 0 .7em;
  font-size:clamp(20px,3vw,28px);color:#fff;
}
.prose h2::before{
  content:"";position:absolute;left:0;top:.3em;bottom:.3em;width:3px;border-radius:2px;
  background:linear-gradient(var(--cyan),var(--amber));
}
.prose h2 > span,.prose h3 > span{position:relative}
.prose h3{font-size:clamp(17px,2.2vw,20px);color:var(--amber);margin-top:1.4em}
.prose p{color:var(--txt)}
.prose ul,.prose ol{padding-left:1.35em;margin:0 0 1.2em;list-style:disc}
.prose ol{list-style:decimal}
.prose li{margin:.35em 0}
.prose a{border-bottom:1px solid rgba(0,229,255,.5)}
.prose strong{color:#fff}
.prose blockquote{
  margin:1.4em 0;padding:14px 18px;border-left:3px solid var(--amber);border-radius:0 4px 4px 0;
  background:rgba(255,181,71,.07);color:#F3E4CB;
}
.prose blockquote p:last-child{margin-bottom:0}
.prose img{border-radius:4px;margin:1.2em 0;border:1px solid var(--line)}
.prose hr{border:0;border-top:1px solid var(--line);margin:2em 0}
.prose table{width:100%;border-collapse:collapse;font-size:16px;margin:1.2em 0}
.prose th,.prose td{border:1px solid var(--line);padding:8px 10px;text-align:left}
.prose code{font-family:var(--mono);font-size:15px;background:rgba(0,229,255,.1);padding:1px 5px;border-radius:3px}

/* ---- 页脚 ---- */
.foot{
  margin-left:var(--rail);margin-top:56px;padding:48px 20px 30px;
  border-top:1px solid var(--line);
  background:linear-gradient(180deg,rgba(0,229,255,.06),rgba(11,16,32,.92));
}
.foot-brand{
  max-width:1120px;margin:0 auto .4em;font-size:clamp(30px,7vw,74px);letter-spacing:.01em;
  color:var(--cyan);
  background:linear-gradient(92deg,var(--cyan),var(--amber));
  -webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;
  overflow-wrap:anywhere;
}
.foot-cols{max-width:1120px;margin:0 auto 26px;display:grid;grid-template-columns:1fr;gap:20px}
.foot-cols dl{padding:0 0 12px;border-bottom:2px solid rgba(0,229,255,.32);border-radius:0 0 4px 4px}
.foot-cols dt{font-size:14px;letter-spacing:.16em;color:var(--amber);margin-bottom:6px}
.foot-cols dd{margin:0}
.foot-cols dd a{display:inline-flex;align-items:center;min-height:40px;padding:2px 0;color:var(--dim);font-size:16px}
.foot-cols dd a:hover{color:#fff}
.foot-cols dd span,.foot-cols dd{color:var(--dim)}
.foot-bar{
  max-width:1120px;margin:0 auto;padding-top:16px;border-top:1px solid var(--line);
  display:flex;flex-wrap:wrap;gap:10px;justify-content:center;align-items:center;
  text-align:center;color:var(--dim);font-size:15px;
}
.foot-bar p{margin:0}
.totop{
  display:inline-flex;align-items:center;justify-content:center;min-height:44px;padding:8px 18px;
  border:1px solid var(--line);border-radius:4px;color:var(--cyan);font-size:15px;
}
.totop:hover{border-color:var(--cyan);background:rgba(0,229,255,.1)}

/* ---- 入场上浮与逐条错峰 ---- */
@media (prefers-reduced-motion: no-preference){
  html.js .reveal{opacity:0;transform:translate3d(0,26px,0)}
  html.js .reveal.in{opacity:1;transform:none;transition:opacity .7s ease,transform .7s cubic-bezier(.22,.8,.24,1)}
  .menu-box menu li,.foot-cols dl{animation:rise .55s cubic-bezier(.22,.8,.24,1) both}
  .menu-box menu li:nth-child(1){animation-delay:.04s}
  .menu-box menu li:nth-child(2){animation-delay:.09s}
  .menu-box menu li:nth-child(3){animation-delay:.14s}
  .menu-box menu li:nth-child(4){animation-delay:.19s}
  .menu-box menu li:nth-child(5){animation-delay:.24s}
  .menu-box menu li:nth-child(6){animation-delay:.29s}
  .menu-box menu li:nth-child(7){animation-delay:.34s}
  .foot-cols dl:nth-child(2){animation-delay:.08s}
  .foot-cols dl:nth-child(3){animation-delay:.16s}
}
@keyframes rise{from{opacity:0;transform:translate3d(0,14px,0)}to{opacity:1;transform:none}}

/* ---- 断点 ---- */
@media (max-width:959px){
  body{padding-top:62px}
  .rail{
    right:0;bottom:auto;top:0;width:auto;height:auto;flex-direction:row;align-items:center;
    gap:8px;padding:8px 12px;border-right:0;border-bottom:1px solid var(--line);
    overflow:hidden;
  }
  .menu-box{margin:0;flex:1 1 auto;overflow:hidden}
  summary{border-bottom:0;padding:0 6px;flex:0 0 auto}
  .menu-box menu{margin:0;flex-direction:row;gap:2px;overflow-x:auto;overflow-y:hidden;padding-bottom:2px}
  .menu-box menu li{flex:0 0 auto}
  .menu-box a{min-height:44px;padding:8px 10px;white-space:nowrap}
  .menu-box a{border-left:0;border-bottom:2px solid transparent}
  .menu-box a:hover{border-left-color:transparent;border-bottom-color:var(--cyan)}
  .hero,main,.foot{margin-left:0}
  .wrap{padding:26px 16px 0}
  .prose > section{padding:28px 0}
  [id]{scroll-margin-top:84px}
}

@media (min-width:960px){
  .wrap{grid-template-columns:192px minmax(0,1fr);gap:38px;padding:52px 30px 0}
  .side{position:sticky;top:26px;align-self:start;border-top:0;border-left:1px solid var(--line);padding:2px 0 0 14px}
  .side-list{flex-direction:column;gap:2px}
  .side-list a{display:flex;padding:6px 0;border-radius:0}
  .foot-cols{grid-template-columns:repeat(3,1fr);gap:26px}
}

@media (min-width:720px) and (max-width:959px){
  .foot-cols{grid-template-columns:repeat(3,1fr)}
}

@media (prefers-reduced-motion: reduce){
  html{scroll-behavior:auto}
  .hero-img{transform:none}
  *{animation-duration:.001s!important;transition-duration:.001s!important}
}

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