:root{
  --paper:#fafaf8;
  --mid:#4a4a4a;
  --ink:#1a1a1a;
  --line:rgba(26,26,26,.24);
  --hair:rgba(26,26,26,.12);
}
*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
html,body{overflow-x:clip}
body{
  margin:0;
  font-size:17px;
  line-height:1.68;
  color:var(--ink);
  background-color:var(--paper);
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='3'/%3E%3C/filter%3E%3Crect width='160' height='160' filter='url(%23n)' opacity='0.075'/%3E%3C/svg%3E");
  font-family:'Be Vietnam Pro','Noto Sans',-apple-system,BlinkMacSystemFont,'PingFang SC','Hiragino Sans GB','Microsoft YaHei',sans-serif;
  font-weight:400;
}
img{display:block;max-width:100%;height:auto}
h1,h2,h3{line-height:1.28;margin:0 0 .55em;font-weight:700;letter-spacing:.01em}
p{margin:0 0 1em}
ul{margin:0 0 1em;padding-left:1.15em}
li{margin:.35em 0}
a{color:var(--ink)}
:focus-visible{outline:2px dashed var(--ink);outline-offset:3px}

h2>span,h3>span{position:relative;display:inline-block;z-index:0}
h2>span::after,h3>span::after{
  content:"";position:absolute;left:-3px;right:-3px;bottom:.04em;height:.4em;
  background:rgba(26,26,26,.14);transform:skewX(-9deg) rotate(-.8deg);z-index:-1;
}

/* 顶栏 */
.topbar{
  position:sticky;top:0;z-index:40;
  background:rgba(250,250,248,.93);
  -webkit-backdrop-filter:blur(6px);backdrop-filter:blur(6px);
  border-bottom:2px dashed var(--line);
}
.mainnav{display:flex;align-items:center;gap:6px;padding:5px clamp(8px,2.4vw,26px)}
.grp{display:flex;flex-wrap:wrap;list-style:none;margin:0;padding:0;gap:2px}
.grp.l{flex:1 1 0;justify-content:flex-start}
.grp.r{flex:1 1 0;justify-content:flex-end}
.mainnav .grp a{
  display:inline-flex;align-items:center;min-height:44px;
  padding:8px 10px;font-size:.95rem;color:var(--mid);text-decoration:none;
  border-bottom:2px solid transparent;
}
.mainnav .grp a::before{
  content:"";width:6px;height:6px;margin-right:7px;
  border:1.5px solid currentColor;border-radius:50%;
  transform:rotate(22deg);opacity:.65;
}
.mainnav .grp a:hover{color:var(--ink);border-bottom-color:var(--ink);transform:rotate(-1deg)}
.mainnav .brand{
  flex:0 0 auto;display:inline-block;padding:9px 15px;
  font-size:1.02rem;font-weight:700;letter-spacing:.16em;color:var(--ink);
  text-decoration:none;background:rgba(255,255,255,.6);
  border:2px solid var(--ink);border-radius:10px;
  transform:rotate(-1.4deg);box-shadow:2px 3px 0 rgba(26,26,26,.14);
}

/* 主体骨架 */
main{display:block}
.wrap{
  max-width:1180px;margin:0 auto;
  padding:0 clamp(14px,3vw,28px);
  display:grid;grid-template-columns:206px minmax(0,1fr);
  gap:clamp(18px,3vw,44px);align-items:start;
}
.rail{position:sticky;top:86px;padding-top:32px}
.rail-h{font-size:1rem;letter-spacing:.2em;margin:0 0 .6em;color:var(--mid)}
.rail nav ul{list-style:none;margin:0;padding:0;border-left:2px dashed var(--line)}
.rail li{margin:0;border-bottom:1px dotted var(--hair)}
.rail a{display:block;padding:11px 12px;font-size:.95rem;color:var(--mid);text-decoration:none;min-height:44px}
.rail a:hover,.rail a[aria-current]{color:var(--ink);background:rgba(26,26,26,.055)}

.flow{min-width:0;padding:22px 0 46px}

/* 头部区块 */
.hero{
  position:relative;isolation:isolate;
  display:grid;grid-template-columns:1fr 1fr;
  gap:clamp(18px,4vw,48px);align-items:center;
  min-height:70vh;padding:22px 0 34px;
}
.ghost{
  position:absolute;inset-inline-start:-1%;top:4%;z-index:-1;
  font-size:clamp(54px,14vw,160px);font-weight:700;line-height:.88;letter-spacing:-.035em;
  color:rgba(26,26,26,.055);white-space:nowrap;transform:rotate(-4deg);
  pointer-events:none;
}
.hero-media{
  transform:rotate(-2.2deg);
  border:2px solid var(--ink);border-radius:10px;
  background:#fff;padding:8px;box-shadow:6px 7px 0 rgba(26,26,26,.12);
}
.hero-media img{width:100%;border-radius:5px;filter:grayscale(.32) contrast(1.06)}
.hero-ph{
  aspect-ratio:4 / 5;
  background:repeating-linear-gradient(45deg,rgba(26,26,26,.09) 0 7px,transparent 7px 15px);
  border-radius:5px;
}
.hero-txt{text-align:center}
.hero-txt h1{
  font-size:clamp(1.95rem,5.4vw,3.3rem);
  letter-spacing:.02em;margin-bottom:.4em;
}
.lead{color:var(--mid);font-size:1.02rem;max-width:34ch;margin:0 auto 1.1em}
.ping{
  display:inline-flex;align-items:center;min-height:44px;
  padding:8px 6px;font-size:.95rem;color:var(--ink);
  text-decoration:none;border-bottom:2px solid var(--ink);
}
.ping::after{content:"›";margin-left:6px;font-size:1.2em;line-height:1}
.ping:hover{background:rgba(26,26,26,.06)}

/* 正文 */
.prose{display:block;padding-top:8px}
.prose>section{
  position:relative;margin:0 0 clamp(24px,4vw,46px);
  padding:clamp(18px,3vw,34px);
  border:2px solid rgba(26,26,26,.82);border-radius:10px;
  background:rgba(255,255,255,.62);
  -webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);
  box-shadow:3px 4px 0 rgba(26,26,26,.1);
  transform:rotate(-.25deg);
}
.prose>section:nth-child(even){transform:rotate(.3deg)}
.prose>section[id]{scroll-margin-top:100px}
.prose h2{font-size:clamp(1.42rem,3.1vw,1.95rem);padding-left:15px;position:relative}
.prose h2::before{
  content:"";position:absolute;left:0;top:.22em;bottom:.22em;width:5px;
  background:var(--ink);transform:rotate(1.6deg);
}
.prose h3{font-size:1.15rem}
.prose a{text-decoration:underline;text-decoration-style:dotted;text-underline-offset:3px}
.prose a:hover{text-decoration-style:solid}
.prose img{border:2px solid var(--ink);border-radius:8px;margin:1em 0}
.prose blockquote{
  margin:1em 0;padding:.6em 0 .6em 1em;
  border-left:4px solid var(--hair);color:var(--mid);
}
.prose code{font-size:.95em;background:rgba(26,26,26,.07);padding:.1em .35em;border-radius:4px}

/* 页脚 */
footer{
  display:flex;flex-wrap:wrap;gap:12px 44px;justify-content:space-between;align-items:flex-start;
  margin-top:40px;padding:26px clamp(14px,3vw,28px) 38px;
  border-top:2px dashed var(--line);background:rgba(26,26,26,.035);
}
footer section{max-width:540px}
footer h2{font-size:1rem;letter-spacing:.18em;color:var(--mid);margin-bottom:.35em}
footer ul{display:flex;flex-wrap:wrap;gap:0 2px;list-style:none;margin:0;padding:0}
footer a{display:inline-block;padding:9px 8px;min-height:44px;font-size:.95rem;color:var(--mid);text-decoration:none}
footer a:hover{color:var(--ink);text-decoration:underline}
footer p{margin:0;padding:10px 0;font-size:.95rem;color:var(--mid)}

/* 动效 */
.rv{opacity:0;translate:0 14px}
.rv.in{opacity:1;translate:0 0;transition:opacity .3s steps(6,end),translate .3s steps(6,end)}

/* 断点 */
@media (max-width:980px){
  .wrap{grid-template-columns:minmax(0,1fr)}
  .rail{display:none}
  .flow{padding-top:12px}
  .prose>section[id]{scroll-margin-top:150px}
}
@media (max-width:840px){
  .mainnav{flex-wrap:wrap;padding:5px 10px 2px}
  .mainnav .brand{order:-1;flex:1 0 100%;text-align:center;margin:5px 0;font-size:1rem}
  .grp,.grp.l,.grp.r{flex:1 1 100%;justify-content:flex-start}
  .mainnav .grp a{padding:8px}
}
@media (max-width:760px){
  .hero{grid-template-columns:minmax(0,1fr);min-height:0;padding:6px 0 24px;gap:20px}
  .hero-txt{order:-1;text-align:left}
  .lead{margin:0 0 1em}
  .ghost{top:0;font-size:clamp(46px,15vw,90px);opacity:.9}
  .hero-media{transform:rotate(-1.3deg)}
  footer{gap:10px 22px}
}
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{animation:none!important;transition:none!important}
  html{scroll-behavior:auto}
  .rv{opacity:1;translate:0 0}
}

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