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

:root{
  --ink:#000000;
  --paper:#ffffff;
  --soft:#f2f2f2;
  --line:#d8d8d8;
  --r:10px;
  --pad:clamp(1.1rem,4vw,3.5rem);
  --font-body:'Poppins',-apple-system,BlinkMacSystemFont,"PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  --font-display:'Righteous','Poppins',-apple-system,"PingFang SC","Microsoft YaHei",sans-serif;
}

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

html{
  scroll-behavior:smooth;
  -webkit-text-size-adjust:100%;
}

body{
  margin:0;
  overflow-x:clip;
  background:var(--paper);
  color:var(--ink);
  font-family:var(--font-body);
  font-size:17px;
  line-height:1.7;
  font-weight:400;
}

img{display:block;max-width:100%;height:auto}
a{color:inherit;text-decoration:none}
p{margin:0 0 1.15em}
ul,menu{margin:0;padding:0;list-style:none}
hr{border:0;border-top:3px solid var(--ink);margin:1.1rem 0 1.6rem}

h1,h2,h3,h4{
  margin:0;
  font-family:var(--font-display);
  font-weight:700;
  letter-spacing:-.035em;
  line-height:1.04;
}

:focus-visible{outline:3px solid var(--ink);outline-offset:3px}

.skip{
  position:absolute;
  left:-9999px;
  top:0;
  z-index:200;
  background:var(--ink);
  color:var(--paper);
  padding:.7rem 1.1rem;
  border-radius:var(--r);
}
.skip:focus{left:1rem;top:.7rem}

/* ---------- 顶栏 ---------- */
.topbar{
  position:sticky;
  top:0;
  z-index:80;
  display:grid;
  grid-template-columns:1fr auto 1fr;
  align-items:center;
  gap:.55rem;
  padding:.65rem var(--pad);
  background:var(--paper);
  border-bottom:3px solid var(--ink);
}

.bar-left{justify-self:start;display:flex;align-items:center;gap:.5rem}
.bar-right{justify-self:end;display:flex;align-items:center;gap:.5rem}

.brand{
  margin:0;
  justify-self:center;
  font-family:var(--font-display);
  font-size:clamp(1.02rem,2.3vw,1.4rem);
  font-weight:400;
  letter-spacing:.01em;
  white-space:nowrap;
}
.brand a{display:block;padding:.4rem .25rem}

.drawer{position:relative}

.drawer>summary{
  list-style:none;
  cursor:pointer;
  display:inline-flex;
  align-items:center;
  gap:.45rem;
  min-height:44px;
  padding:.4rem .85rem;
  font-size:1rem;
  font-weight:600;
  border:2px solid var(--ink);
  border-radius:var(--r);
  transition:background .18s ease,color .18s ease,box-shadow .18s ease,transform .18s ease;
}
.drawer>summary::-webkit-details-marker{display:none}
.drawer>summary::after{
  content:"";
  width:8px;
  height:8px;
  border-right:2px solid currentColor;
  border-bottom:2px solid currentColor;
  transform:rotate(45deg) translateY(-2px);
  transition:transform .18s ease;
}
.drawer>summary:hover{transform:translate(-1px,-1px);box-shadow:3px 3px 0 var(--ink)}
.drawer[open]>summary{background:var(--ink);color:var(--paper)}
.drawer[open]>summary::after{transform:rotate(-135deg) translateY(-2px)}

.drawer menu{
  position:absolute;
  top:calc(100% + .55rem);
  left:0;
  min-width:12rem;
  padding:.45rem;
  background:var(--ink);
  color:var(--paper);
  border-radius:var(--r);
  box-shadow:10px 10px 0 rgba(0,0,0,.16);
}
.bar-right .drawer menu{left:auto;right:0}
.drawer menu li a{
  display:flex;
  align-items:center;
  min-height:44px;
  padding:.5rem .8rem;
  border-radius:6px;
  font-size:1rem;
  color:var(--paper);
  transition:background .15s ease,color .15s ease;
}
.drawer menu li a:hover,.drawer menu li a:focus-visible{background:var(--paper);color:var(--ink)}

.contact{
  display:inline-flex;
  align-items:center;
  min-height:44px;
  padding:.4rem .95rem;
  font-size:1rem;
  font-weight:600;
  background:var(--ink);
  color:var(--paper);
  border:2px solid var(--ink);
  border-radius:var(--r);
  transition:background .18s ease,color .18s ease,box-shadow .18s ease,transform .18s ease;
}
.contact:hover{background:var(--paper);color:var(--ink);transform:translate(-1px,-1px);box-shadow:3px 3px 0 var(--ink)}

/* ---------- 主区 ---------- */
main{display:block}
main section[id]{scroll-margin-top:104px}

.hero{
  display:grid;
  grid-template-columns:minmax(0,.85fr) minmax(0,1.15fr);
  align-items:center;
  gap:clamp(1.4rem,4vw,4rem);
  min-height:70vh;
  padding:clamp(2rem,6vw,5rem) var(--pad);
  border-bottom:3px solid var(--ink);
}

.hero-fig{
  position:relative;
  margin:0;
  display:flex;
  align-items:center;
  justify-content:center;
  aspect-ratio:4 / 5;
  overflow:hidden;
  border-radius:var(--r);
  background:var(--ink);
}
.hero-fig img{width:100%;height:100%;object-fit:cover;filter:grayscale(1) contrast(1.06)}
.fig-type{
  font-family:var(--font-display);
  font-size:clamp(3.5rem,11vw,8rem);
  line-height:1;
  color:var(--paper);
  letter-spacing:-.05em;
}
.badge{
  position:absolute;
  left:.75rem;
  bottom:.75rem;
  padding:.25rem .8rem;
  font-size:1rem;
  font-weight:600;
  letter-spacing:.03em;
  color:var(--ink);
  background:var(--paper);
  border:2px solid var(--ink);
  border-radius:999px;
}

.hero-copy{text-align:center}
.hero-copy h1{
  font-size:clamp(2.2rem,5.4vw,4.6rem);
  font-weight:700;
  letter-spacing:-.045em;
  line-height:1.02;
  word-break:break-word;
}
.hero-desc{
  max-width:34ch;
  margin:1.1rem auto 0;
  font-size:clamp(1rem,1.7vw,1.1rem);
  line-height:1.78;
}

/* ---------- 正文 + 侧栏 ---------- */
.content-grid{
  display:grid;
  grid-template-columns:minmax(0,1fr) 15.5rem;
  gap:clamp(1.4rem,4vw,3.5rem);
  align-items:start;
  padding:clamp(2rem,5vw,4rem) var(--pad);
}

.prose{min-width:0}
.prose>section{
  padding:clamp(1.5rem,3.4vw,2.6rem);
  margin-bottom:clamp(1.6rem,4vw,3rem);
  border:2px solid var(--ink);
  border-bottom:12px solid var(--ink);
  border-radius:var(--r);
}
.prose>section:last-child{margin-bottom:0}

.prose h2{
  font-size:clamp(1.55rem,3.3vw,2.5rem);
  letter-spacing:-.03em;
}
.prose h2+hr{margin-top:.7rem;border-top-width:4px}
.prose h3{
  font-size:clamp(1.15rem,2vw,1.45rem);
  margin:1.8rem 0 .55rem;
}
.prose p,.prose li{font-size:1.05rem;line-height:1.85;max-width:66ch}
.prose ul{list-style:disc}
.prose ol{list-style:decimal}
.prose ul,.prose ol{padding-left:1.35rem;margin:0 0 1.2em}
.prose li{margin-bottom:.5rem}
.prose blockquote{
  margin:1.6rem 0;
  padding:1rem 1.2rem;
  border-left:10px solid var(--ink);
  background:var(--soft);
}
.prose blockquote p:last-child{margin-bottom:0}
.prose figure{margin:1.6rem 0}
.prose figure img{border-radius:var(--r)}
.prose a{
  text-decoration:underline;
  text-underline-offset:4px;
  text-decoration-thickness:2px;
}
.prose a:hover{background:var(--ink);color:var(--paper);text-decoration:none}
.prose table{width:100%;border-collapse:collapse;margin:1.4rem 0;font-size:1rem}
.prose th,.prose td{border:2px solid var(--ink);padding:.55rem .7rem;text-align:left}
.prose th{background:var(--soft)}
.prose code{
  font-family:ui-monospace,Menlo,Consolas,monospace;
  font-size:.95em;
  background:var(--soft);
  padding:.1em .38em;
  border-radius:4px;
}

.toc{
  position:sticky;
  top:104px;
  padding:1.1rem 1.1rem 1.3rem;
  border:2px solid var(--ink);
  border-radius:var(--r);
}
.toc h2{font-size:1.05rem;letter-spacing:.01em}
.toc hr{border-top:2px solid var(--ink);margin:.6rem 0 .8rem}
.toc ul li+li{margin-top:.1rem}
.toc a{
  display:flex;
  align-items:center;
  min-height:40px;
  padding:.4rem .1rem;
  font-size:1rem;
  line-height:1.4;
  border-bottom:1px solid var(--line);
  transition:padding-left .16s ease;
}
.toc a:hover{padding-left:.4rem;border-bottom-color:var(--ink)}

/* ---------- 页脚 ---------- */
.foot{
  display:grid;
  grid-template-columns:1.6fr 1fr 1fr 1fr;
  gap:clamp(1.2rem,3vw,2.4rem);
  padding:clamp(2.5rem,6vw,4.5rem) var(--pad) 1.4rem;
  border-top:3px solid var(--ink);
}
.foot-mark{
  display:block;
  font-family:var(--font-display);
  font-style:normal;
  font-size:clamp(1.6rem,4.4vw,2.6rem);
  font-weight:700;
  letter-spacing:-.035em;
  line-height:1.05;
}
.foot ul{display:flex;flex-direction:column}
.foot ul li+li{margin-top:.15rem}
.foot ul a{
  display:inline-flex;
  align-items:center;
  min-height:40px;
  padding:.15rem 0;
  font-size:1rem;
  border-bottom:2px solid transparent;
}
.foot ul a:hover{border-bottom-color:var(--ink)}
.foot-base{
  grid-column:1 / -1;
  margin-top:1.4rem;
  padding-top:1.2rem;
  text-align:center;
  font-size:1rem;
  letter-spacing:.02em;
  border-top:2px solid var(--ink);
}

/* ---------- 动效 ---------- */
.js .reveal{
  opacity:0;
  transform:translateY(20px);
  transition:opacity .6s ease,transform .6s ease;
}
.js .reveal.in{opacity:1;transform:none}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{transition:none!important;animation:none!important}
  .js .reveal{opacity:1;transform:none}
}

/* ---------- 断点 ---------- */
@media (max-width:900px){
  .toc{top:auto}
  .foot{grid-template-columns:1fr 1fr}
  .foot-id{grid-column:1 / -1}
}

@media (max-width:860px){
  .topbar{
    display:flex;
    flex-wrap:wrap;
    justify-content:space-between;
    align-items:center;
    row-gap:.5rem;
    padding:.6rem 1rem;
  }
  .brand{order:-1;width:100%;text-align:center}
  .bar-left{order:1}
  .bar-right{order:2}
  .hero{
    grid-template-columns:minmax(0,1fr);
    min-height:0;
    padding-top:1.5rem;
    gap:1.3rem;
  }
  .hero-copy{order:-1}
  .hero-fig{aspect-ratio:16 / 10}
  .content-grid{grid-template-columns:minmax(0,1fr)}
  .toc{order:-1}
  main section[id]{scroll-margin-top:150px}
}

@media (max-width:520px){
  .prose>section{padding:1.15rem;border-bottom-width:10px}
  .foot{grid-template-columns:1fr}
  .foot-id{grid-column:auto}
  .drawer menu{min-width:10.5rem}
}

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