@import url('https://fonts.googleapis.com/css2?family=Didact+Gothic&family=Poiret+One&display=swap');

:root{
  --mint:#b4fde1;
  --sky:#add8e6;
  --ink:#172620;
  --mint-2:#8ff0cd;
  --sky-2:#93c8dc;
  --clay: inset -4px -4px 10px rgba(23,38,32,.14), inset 4px 4px 12px rgba(255,255,255,.85), 6px 7px 0 rgba(23,38,32,.15);
  --clay-sm: inset -2px -2px 6px rgba(23,38,32,.12), inset 2px 2px 8px rgba(255,255,255,.8), 3px 4px 0 rgba(23,38,32,.14);
  --clay-out: 6px 8px 0 rgba(23,38,32,.16);
  --font-b:'Didact Gothic',"PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  --font-d:'Poiret One',"PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
}

*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  margin:0;
  font-family:var(--font-b);
  font-size:17px;
  line-height:1.75;
  color:var(--ink);
  background:linear-gradient(180deg,#e9fbf3 0%,#ddf2fa 42%,#f4fffb 100%);
  background-attachment:fixed;
  overflow-x:hidden;
}
img{max-width:100%;height:auto;display:block}
a{color:var(--ink);text-decoration-thickness:2px;text-underline-offset:3px}
:focus-visible{outline:3px solid var(--ink);outline-offset:3px}
[id]{scroll-margin-top:104px}

/* 顶栏 */
.topbar{
  position:sticky;top:0;z-index:60;
  display:flex;align-items:center;gap:12px;
  padding:10px clamp(12px,3vw,28px);
  background:linear-gradient(180deg,#f6fffb,#ddf6ec);
  border-bottom:4px solid var(--ink);
  box-shadow:0 6px 0 rgba(23,38,32,.10);
}
.brand{
  display:inline-flex;align-items:center;gap:8px;
  min-height:44px;padding:5px 12px 5px 5px;
  border:3px solid var(--ink);border-radius:16px;
  background:var(--mint);box-shadow:var(--clay-sm);
  text-decoration:none;white-space:nowrap;
  font-family:var(--font-d);font-size:18px;letter-spacing:.06em;
}
.brand-mark{
  display:grid;place-items:center;width:28px;height:28px;
  border:2px solid var(--ink);border-radius:10px;
  background:var(--sky);font-family:var(--font-d);font-size:15px;
}
.nav{flex:1;min-width:0}
.nav-row{display:flex;flex-wrap:wrap;gap:4px;margin:0;justify-content:center}
.nav-row a{
  display:inline-flex;align-items:center;min-height:44px;
  padding:6px 12px;border:3px solid transparent;border-radius:14px;
  text-decoration:none;font-size:16px;
  transition:background .2s ease-out,border-color .2s ease-out,box-shadow .2s ease-out;
}
.nav-row a:hover{background:#fff;border-color:var(--ink);box-shadow:var(--clay-sm)}
.cta{
  display:inline-flex;align-items:center;min-height:44px;
  padding:8px 18px;border:3px solid var(--ink);border-radius:999px;
  background:var(--sky);box-shadow:var(--clay-sm);
  text-decoration:none;font-weight:700;white-space:nowrap;
  transition:transform .2s ease-out,box-shadow .2s ease-out;
}
.cta:active{transform:translateY(3px);box-shadow:none}

/* 头部大标题区 */
.hero{
  position:relative;overflow:hidden;
  display:grid;grid-template-columns:minmax(0,260px) minmax(0,1fr);
  align-items:center;gap:clamp(14px,3vw,40px);
  min-height:45vh;
  padding:clamp(18px,4vw,38px) clamp(14px,4vw,48px) 26px;
}
.hero::before{
  content:"01";
  position:absolute;left:44%;top:-14%;
  font-family:var(--font-d);line-height:1;
  font-size:clamp(90px,18vw,190px);
  color:rgba(23,38,32,.07);
  pointer-events:none;
}
.hero-art{position:relative;margin:0;z-index:1}
.blob{width:100%;max-width:200px;height:auto;animation:bob 6s ease-in-out infinite}
@keyframes bob{
  0%,100%{transform:translateY(0) rotate(-2deg)}
  50%{transform:translateY(-10px) rotate(2deg)}
}
.hero-img{
  margin-top:-16px;
  border:4px solid var(--ink);border-radius:24px;
  box-shadow:var(--clay-out);background:#fff;
}
.hero-text{text-align:right}
.hero h1{
  font-family:var(--font-d);
  font-size:clamp(29px,5.6vw,52px);
  line-height:1.16;letter-spacing:.02em;
  margin:0 0 12px;
}
.lede{margin:0 0 0 auto;max-width:34ch;color:#26443a;font-size:17px}

/* 主体 */
.shell{
  display:grid;grid-template-columns:minmax(0,1fr) 286px;
  align-items:start;gap:clamp(16px,3vw,32px);
  padding:0 clamp(14px,4vw,48px) 56px;
}
.prose{min-width:0;overflow-wrap:break-word}
.prose > article{
  margin:0 0 22px;padding:clamp(16px,3vw,30px);
  border:3px solid var(--ink);border-radius:0;
  border-bottom-width:8px;border-bottom-color:var(--sky-2);
  background:linear-gradient(180deg,#ffffff,#f0fffa);
  box-shadow:inset -3px -3px 10px rgba(23,38,32,.10), inset 3px 3px 10px #fff, 5px 6px 0 rgba(23,38,32,.12);
}
.prose h2{
  font-family:var(--font-d);
  font-size:clamp(22px,3.2vw,30px);
  line-height:1.32;letter-spacing:.02em;
  margin:.1em 0 .7em;
}
.prose h2 span{display:inline-block;padding:0 12px 4px;border-bottom:4px solid var(--mint-2)}
.prose h3{font-size:20px;line-height:1.4;margin:1.3em 0 .5em}
.prose h3 span{display:inline-block;padding-left:11px;border-left:6px solid var(--sky)}
.prose p{margin:0 0 1em}
.prose ul,.prose ol{margin:0 0 1em;padding-left:1.35em}
.prose li{margin:.4em 0}
.prose a{font-weight:700}
.prose figure{
  margin:1em 0;padding:10px;
  border:3px solid var(--ink);border-radius:16px;
  background:#eefcf6;box-shadow:var(--clay-sm);
}
.prose figcaption{font-size:15px;color:#2b4a3f;padding-top:6px}
.prose blockquote{
  margin:1em 0;padding:12px 18px;
  border-left:8px solid var(--mint-2);border-radius:0 16px 16px 0;
  background:#f2fffb;
}
.prose blockquote p:last-child{margin:0}
.prose table{width:100%;border-collapse:collapse;font-size:16px;display:block;overflow-x:auto}
.prose th,.prose td{border:2px solid rgba(23,38,32,.28);padding:8px 10px;text-align:left}
.prose th{background:#e6f8f0}
.prose code{background:#e6f8f0;padding:1px 5px;border-radius:6px;font-size:15px}
.prose hr{border:0;border-top:3px dashed rgba(23,38,32,.28);margin:20px 0}

/* 侧栏 */
.side{position:sticky;top:104px;display:grid;gap:14px}
.side-box{
  padding:14px 16px;
  border:3px solid var(--ink);border-radius:20px;
  background:linear-gradient(180deg,#eefbff,#dbf1fb);
  box-shadow:var(--clay);
}
.side-box h2,.side-box h3{
  font-family:var(--font-d);font-size:17px;letter-spacing:.12em;
  margin:0 0 10px;
}
.side-box h2 span,.side-box h3 span{display:inline-block;padding-bottom:2px;border-bottom:3px solid var(--mint-2)}
.toc{list-style:none;margin:0;padding:0;counter-reset:t}
.toc li{counter-increment:t}
.toc a{
  display:flex;align-items:center;gap:9px;
  min-height:40px;padding:4px 6px;border-radius:12px;
  text-decoration:none;font-size:16px;
  transition:background .2s ease-out,box-shadow .2s ease-out;
}
.toc a::before{
  content:counter(t,decimal-leading-zero);
  font-family:var(--font-d);font-size:13px;color:#3f6155;
}
.toc a:hover{background:#fff;box-shadow:var(--clay-sm)}
.side-note p{margin:0;font-size:16px;color:#2b4a3f}
.to-top{
  display:inline-flex;align-items:center;justify-content:center;
  min-height:44px;border:3px solid var(--ink);border-radius:999px;
  background:var(--mint);box-shadow:var(--clay-sm);
  text-decoration:none;font-weight:700;
  transition:transform .2s ease-out,box-shadow .2s ease-out;
}
.to-top:active{transform:translateY(3px);box-shadow:none}

/* 页脚 */
.foot{
  border-top:4px solid var(--ink);
  background:linear-gradient(180deg,#ddf6ec,#c6ead9);
  padding:30px clamp(14px,4vw,48px) 18px;
}
.foot-cols{display:grid;grid-template-columns:minmax(0,1.1fr) minmax(0,1.7fr);gap:24px}
.foot-logo{
  display:inline-flex;align-items:center;min-height:44px;
  font-family:var(--font-d);font-size:20px;letter-spacing:.06em;
  text-decoration:none;
}
.foot-brand p{margin:6px 0 0;font-size:16px;color:#254238;max-width:34ch}
.foot-links{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px}
.foot dl{margin:0}
.foot dt{
  display:inline-block;margin-bottom:8px;
  font-family:var(--font-d);font-size:16px;letter-spacing:.12em;
  border-bottom:3px solid var(--mint-2);
}
.foot dd{margin:0}
.foot dd a{display:flex;align-items:center;min-height:40px;padding:3px 0;font-size:16px;text-decoration:none}
.foot dd a:hover{text-decoration:underline}
.copy{
  margin:22px 0 0;padding-top:12px;
  border-top:2px dashed rgba(23,38,32,.3);
  font-size:15px;color:#2c4a40;
}

/* 动效 */
@media (prefers-reduced-motion: no-preference){
  .js .reveal{opacity:.001;transform:translateY(14px)}
  .js .reveal.in{
    opacity:1;transform:none;
    transition:opacity .45s ease-out,transform .5s cubic-bezier(.34,1.56,.64,1);
  }
  .js .toc li:nth-child(2){transition-delay:.05s}
  .js .toc li:nth-child(3){transition-delay:.1s}
  .js .toc li:nth-child(4){transition-delay:.15s}
}
@media (prefers-reduced-motion: reduce){
  html{scroll-behavior:auto}
  .blob{animation:none}
  .js .reveal{opacity:1;transform:none}
}

@media (max-width: 980px){
  .shell{grid-template-columns:minmax(0,1fr)}
  .side{position:static;grid-template-columns:repeat(2,minmax(0,1fr));align-items:start}
  .to-top{grid-column:1 / -1}
}

@media (max-width: 720px){
  body{font-size:16px}
  .topbar{position:static;flex-wrap:wrap;gap:8px;padding:10px 12px}
  .nav{order:3;flex-basis:100%}
  .nav-row{
    flex-wrap:nowrap;justify-content:flex-start;
    overflow-x:auto;padding-bottom:4px;
  }
  .nav-row a{white-space:nowrap;background:#fff;border-color:rgba(23,38,32,.22)}
  .cta{padding:8px 14px}
  .hero{grid-template-columns:minmax(0,1fr);min-height:0;gap:10px;padding:16px 14px 22px}
  .hero::before{font-size:78px;top:-4%;left:auto;right:6%}
  .hero-text{order:-1;text-align:left}
  .lede{max-width:none}
  .hero-art{max-width:150px}
  .shell{padding:0 12px 40px}
  .side{grid-template-columns:minmax(0,1fr)}
  .foot-cols{grid-template-columns:minmax(0,1fr)}
  .foot-links{grid-template-columns:repeat(auto-fit,minmax(88px,1fr))}
  [id]{scroll-margin-top:16px}
}

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