:root{
  --black:#000000;
  --coal:#121212;
  --ink:#000000;
  --txt:#e9eef4;
  --dim:#98a3ae;
  --faint:#77828d;
  --line:rgba(255,255,255,.13);
  --glass:rgba(255,255,255,.05);
  --neon:#4cd7ff;
  --r:18px;
  --head:78px;
}
*{box-sizing:border-box}
html{
  background-color:var(--black);
  background-image:
    radial-gradient(1100px 560px at 78% -10%, #0c1524 0%, rgba(0,0,0,0) 70%),
    radial-gradient(900px 620px at -6% 104%, #0a1119 0%, rgba(0,0,0,0) 62%);
  color-scheme:dark;
  scroll-behavior:smooth;
  -webkit-text-size-adjust:100%;
}
body{
  margin:0;
  font-family:'Atkinson Hyperlegible','Segoe UI',system-ui,-apple-system,'Noto Sans SC',sans-serif;
  font-size:17px;
  line-height:1.75;
  color:var(--txt);
  overflow-x:hidden;
  overflow-wrap:anywhere;
  -webkit-font-smoothing:antialiased;
}
body::before{
  content:"";
  position:fixed;
  inset:0;
  z-index:-1;
  pointer-events:none;
  background-image:radial-gradient(rgba(255,255,255,.075) 1px, transparent 1px);
  background-size:28px 28px;
  -webkit-mask-image:linear-gradient(180deg, rgba(0,0,0,.9), rgba(0,0,0,.22) 55%, transparent);
  mask-image:linear-gradient(180deg, rgba(0,0,0,.9), rgba(0,0,0,.22) 55%, transparent);
}
a{color:inherit}
img{max-width:100%}
:focus-visible{outline:2px dashed var(--neon);outline-offset:3px;border-radius:8px}

/* 顶栏 */
.top{
  position:sticky;
  top:0;
  z-index:40;
  display:flex;
  align-items:center;
  gap:16px;
  padding:12px clamp(14px,3vw,32px);
  min-height:var(--head);
  background:rgba(0,0,0,.74);
  -webkit-backdrop-filter:blur(16px) saturate(140%);
  backdrop-filter:blur(16px) saturate(140%);
  border-bottom:1px solid var(--line);
}
.mark{
  display:inline-flex;
  align-items:center;
  gap:10px;
  min-height:44px;
  flex:0 0 auto;
  text-decoration:none;
  color:#fff;
}
.mark-txt{
  font-size:18px;
  font-weight:700;
  letter-spacing:.02em;
  text-shadow:0 0 16px rgba(76,215,255,.35);
}
.mark-img{display:block;border-radius:10px}
.bar{
  display:flex;
  align-items:center;
  gap:14px;
  flex:1 1 auto;
  min-width:0;
  margin-left:auto;
}
.menu{min-width:0;overflow-x:auto;scrollbar-width:none}
.menu::-webkit-scrollbar{display:none}
.menu ul{display:flex;gap:6px;margin:0;padding:4px;list-style:none}
.menu a{
  display:inline-flex;
  align-items:center;
  gap:8px;
  min-height:44px;
  padding:8px 14px;
  border-radius:999px;
  border:1px solid transparent;
  font-size:16px;
  color:var(--dim);
  text-decoration:none;
  white-space:nowrap;
  transition:color .22s,background .22s,border-color .22s;
}
.menu a:hover,
.menu a:focus-visible,
.menu a.is-on{
  color:#fff;
  background:rgba(255,255,255,.07);
  border-color:var(--line);
}
.tick{
  width:5px;
  height:5px;
  flex:0 0 auto;
  border-radius:50%;
  background:var(--neon);
  box-shadow:0 0 8px var(--neon);
  opacity:.45;
  transition:opacity .22s;
}
.menu a:hover .tick,
.menu a.is-on .tick{opacity:1}
.menu li.is-off{display:none}
.find{display:flex;align-items:center;gap:8px;margin:0;flex:0 0 auto}
.find-lab{font-size:16px;color:var(--faint)}
.find-in{
  width:152px;
  min-height:44px;
  padding:8px 15px;
  border-radius:999px;
  border:1px solid var(--line);
  background:rgba(255,255,255,.05);
  color:var(--txt);
  font:inherit;
  font-size:16px;
}
.find-in::placeholder{color:#6d7883}
.find-in:focus{background:rgba(255,255,255,.09)}

/* 首屏 */
.hero{
  position:relative;
  min-height:calc(100svh - var(--head));
  display:grid;
  grid-template-rows:1fr auto;
  gap:clamp(20px,4vw,44px);
  padding:clamp(26px,5vw,72px) clamp(18px,5vw,56px) 0;
  overflow:hidden;
}
.hero-copy{align-self:end;max-width:56ch}
h1{
  margin:0 0 18px;
  font-size:clamp(30px,5vw,56px);
  line-height:1.18;
  letter-spacing:-.015em;
  text-shadow:0 0 26px rgba(76,215,255,.22);
}
.lede{margin:0;max-width:52ch;color:var(--dim);font-size:17px}
.hero-fig{
  margin:0;
  position:relative;
  display:flex;
  align-items:flex-end;
  justify-content:center;
  min-height:200px;
  max-height:46svh;
  overflow:hidden;
  border-top:1px solid var(--line);
  border-radius:var(--r) var(--r) 0 0;
  background-image:radial-gradient(rgba(255,255,255,.1) 1px, transparent 1px);
  background-size:26px 26px;
}
.hero-fig::after{
  content:"";
  position:absolute;
  inset:auto 0 0 0;
  height:60%;
  background:linear-gradient(180deg, rgba(0,0,0,0), #000 92%);
  pointer-events:none;
}
.hero-shot{
  display:block;
  width:100%;
  height:auto;
  object-fit:cover;
  border-radius:var(--r) var(--r) 0 0;
}
.hero-slim{min-height:auto;padding-bottom:clamp(24px,4vw,48px)}

/* 主舞台：左侧工具条 + 正文 */
.stage{
  display:grid;
  grid-template-columns:56px minmax(0,1fr);
  gap:clamp(16px,3vw,36px);
  max-width:1080px;
  margin:0 auto;
  padding:clamp(28px,4vw,56px) clamp(16px,4vw,32px) clamp(40px,6vw,80px);
}
.rail{
  position:sticky;
  top:calc(var(--head) + 20px);
  align-self:start;
  display:flex;
  flex-direction:column;
  gap:10px;
}
.rail-top{
  display:flex;
  align-items:center;
  justify-content:center;
  min-height:136px;
  padding:16px 8px;
  border:1px solid var(--line);
  border-radius:999px;
  background:var(--glass);
  -webkit-backdrop-filter:blur(8px);
  backdrop-filter:blur(8px);
  color:var(--dim);
  font-size:16px;
  text-decoration:none;
  transition:color .24s,border-color .24s,background .24s;
}
.rail-top span{writing-mode:vertical-rl;letter-spacing:.2em}
.rail-top:hover{color:#fff;border-color:rgba(76,215,255,.5);background:rgba(76,215,255,.1)}

.flow{min-width:0}
.flow > article{
  position:relative;
  margin:0 0 22px;
  padding:clamp(20px,3vw,34px);
  border:1px solid var(--line);
  border-radius:var(--r);
  background:linear-gradient(180deg, rgba(255,255,255,.055), rgba(255,255,255,.018));
  -webkit-backdrop-filter:blur(10px);
  backdrop-filter:blur(10px);
  scroll-margin-top:calc(var(--head) + 18px);
  transition:border-color .3s, background .3s;
}
.flow > article:hover{
  border-color:rgba(255,255,255,.24);
  background:linear-gradient(180deg, rgba(255,255,255,.075), rgba(255,255,255,.025));
}
.flow h2{
  margin:0 0 14px;
  font-size:clamp(21px,2.4vw,28px);
  line-height:1.32;
  letter-spacing:-.01em;
}
.flow h2 > span{
  background:linear-gradient(transparent 62%, rgba(76,215,255,.26) 62%);
  padding-bottom:2px;
}
.flow h3{margin:26px 0 10px;font-size:19px;line-height:1.4}
.flow h3 > span{color:#fff}
.flow p{margin:0 0 14px;color:#ccd5de}
.flow ul,.flow ol{margin:0 0 16px;padding-left:22px;color:#ccd5de}
.flow li{margin:6px 0}
.flow a{color:var(--neon);text-underline-offset:3px}
.flow strong{color:#fff}
.flow blockquote{
  margin:18px 0;
  padding:12px 18px;
  border-left:2px solid var(--neon);
  border-radius:0 14px 14px 0;
  background:rgba(255,255,255,.04);
}
.flow img{height:auto;border-radius:14px}
.flow figure{margin:18px 0}
.flow figcaption{color:var(--faint);font-size:16px;margin-top:6px}
.flow table{
  display:block;
  width:100%;
  overflow-x:auto;
  border-collapse:collapse;
  font-size:16px;
}
.flow th,.flow td{border:1px solid var(--line);padding:10px 12px;text-align:left}
.flow th{background:rgba(255,255,255,.05);color:#fff}

/* 页脚 */
.foot{
  display:flex;
  flex-wrap:wrap;
  align-items:flex-start;
  gap:30px;
  padding:48px clamp(18px,4vw,48px) 34px;
  border-top:1px solid var(--line);
  background:linear-gradient(180deg, rgba(18,18,18,.72), #000 88%);
}
.foot-brand{flex:1 1 300px;min-width:0}
.foot-brand h2{margin:0;font-size:clamp(36px,7vw,64px);line-height:1;letter-spacing:-.025em}
.foot-brand h2 span{text-shadow:0 0 30px rgba(76,215,255,.2)}
.foot-brand a{color:#fff;text-decoration:none}
.foot-col{flex:0 1 auto}
.foot-nav ul{
  display:grid;
  grid-template-columns:repeat(2,minmax(0,1fr));
  gap:0 18px;
  margin:0;
  padding:0;
  list-style:none;
}
.foot-nav a{
  display:inline-flex;
  align-items:center;
  min-height:42px;
  padding:6px 2px;
  font-size:16px;
  color:var(--dim);
  text-decoration:none;
}
.foot-nav a:hover{color:#fff}
.foot-h{margin:0;font-size:17px;color:var(--txt)}
.foot-h > span{
  background:linear-gradient(transparent 62%, rgba(76,215,255,.26) 62%);
  padding-bottom:2px;
}
.kw{margin:6px 0 0;max-width:13em;font-size:16px;color:var(--faint)}
.foot-copy{margin-left:auto}
.foot-copy p{margin:0;font-size:16px;color:var(--faint)}

/* 动效 */
@media (prefers-reduced-motion: no-preference){
  .menu li{
    opacity:0;
    animation:navpop .5s cubic-bezier(.2,.7,.3,1) forwards;
    animation-delay:calc(var(--n) * 45ms);
  }
  @keyframes navpop{
    from{opacity:0;transform:translateY(-6px)}
    to{opacity:1;transform:none}
  }
  .flow > article{
    animation:rise .55s cubic-bezier(.2,.7,.3,1) both;
  }
  @keyframes rise{
    from{opacity:0;transform:translateY(14px)}
    to{opacity:1;transform:none}
  }
}
@media (prefers-reduced-motion: reduce){
  html{scroll-behavior:auto}
  .menu li,.flow > article{animation:none;opacity:1}
}

/* 断点 */
@media (max-width:760px){
  :root{--head:118px}
  .top{flex-wrap:wrap;gap:8px;padding:8px 14px;align-items:center}
  .bar{
    order:3;
    flex:1 1 100%;
    flex-direction:column;
    align-items:stretch;
    gap:8px;
    margin:0;
  }
  .menu ul{padding:0 0 4px}
  .menu a{padding:10px 13px}
  .find{width:100%}
  .find-in{width:100%}
  .hero{min-height:auto;padding:22px 16px 0}
  .hero-fig{max-height:none;min-height:170px}
  .stage{grid-template-columns:1fr;gap:0;padding:24px 14px 44px}
  .rail{display:none}
  .flow > article{padding:20px 16px;border-radius:16px;scroll-margin-top:calc(var(--head) + 12px)}
  .foot{padding:34px 16px 26px;gap:18px}
  .foot-brand,.foot-col,.foot-copy{flex:1 1 100%;margin-left:0}
}
@media (min-width:761px) and (max-width:1000px){
  .find-in{width:120px}
  .find-lab{display:none}
}

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