@import url('https://fonts.googleapis.com/css2?family=Nunito+Sans:wght@300;400;500;600;700&family=Varela+Round&display=swap');

:root{
  --paper:#fdfbf7;
  --panel:#f5f5f5;
  --ink:#1a1a1a;
  --line:#e2ded6;
  --soft:#8b857c;
  --glass:rgba(253,251,247,.74);
  --r:10px;
  --display:"Varela Round","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  --text:"Nunito Sans","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  --mono:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
}

*{box-sizing:border-box}

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

body{
  margin:0;
  background:var(--paper);
  color:var(--ink);
  font:400 17px/1.75 var(--text);
  letter-spacing:.01em;
  overflow-x:clip;
  max-width:100%;
}

body::before{
  content:"";
  position:fixed;
  inset:0;
  z-index:0;
  pointer-events:none;
  opacity:.5;
  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='0.82' numOctaves='2'/%3E%3CfeColorMatrix type='saturate' values='0'/%3E%3C/filter%3E%3Crect width='160' height='160' filter='url(%23n)' opacity='0.26'/%3E%3C/svg%3E");
}

body > *{position:relative;z-index:1}

a{
  color:var(--ink);
  text-decoration:underline;
  text-decoration-thickness:1px;
  text-underline-offset:.22em;
  text-decoration-color:#b8b2a7;
}

a:hover{text-decoration-color:var(--ink)}
a:focus-visible{outline:2px solid var(--ink);outline-offset:3px;border-radius:3px}
::selection{background:var(--ink);color:var(--paper)}

img{max-width:100%;height:auto;display:block}

hr{
  border:0;
  border-top:2px solid var(--ink);
  width:56px;
  margin:.85rem 0 1.35rem;
}

/* 顶部细条 */
.strip{
  background:var(--ink);
  color:var(--paper);
  font-size:1rem;
  line-height:1;
  letter-spacing:.34em;
  text-indent:.34em;
  padding:.5rem 1rem;
  text-align:center;
}

.strip-in{margin:0;font-size:.95rem}

/* 刊头 */
.masthead{
  position:sticky;
  top:0;
  z-index:30;
  background:var(--glass);
  backdrop-filter:blur(10px) saturate(1.05);
  border-bottom:1px solid var(--line);
}

.mainnav{
  max-width:1160px;
  margin:0 auto;
  padding:.15rem 1rem;
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:.1rem .5rem;
}

.navlist{display:contents;margin:0;padding:0;list-style:none}

.navlist > li{order:1}
.navlist > li:nth-child(n+4){order:3}
.brandmark{order:2}

.navlist a{
  display:inline-flex;
  align-items:center;
  min-height:44px;
  padding:0 .45rem;
  font-size:1rem;
  text-decoration:none;
  white-space:nowrap;
}

.navlist a:hover,
.navlist a:focus-visible{
  text-decoration:underline;
  text-decoration-thickness:1px;
  text-underline-offset:.4em;
  text-decoration-color:var(--ink);
}

.brandmark{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  min-height:44px;
  padding:0 .5rem;
  font-family:var(--display);
  font-size:1.15rem;
  letter-spacing:.16em;
  text-decoration:none;
  border-left:1px solid var(--line);
  border-right:1px solid var(--line);
}

.brandmark .logo{height:30px;width:auto;filter:grayscale(1)}

/* 首屏 */
.hero{
  position:relative;
  overflow:hidden;
  border-bottom:1px solid var(--line);
  min-height:70vh;
  display:flex;
  align-items:center;
}

.hero::before{
  content:"";
  position:absolute;
  inset:0;
  background-image:radial-gradient(var(--ink) 1px,transparent 1px);
  background-size:20px 20px;
  opacity:.16;
  -webkit-mask-image:radial-gradient(120% 92% at 44% 42%,#000 26%,transparent 76%);
  mask-image:radial-gradient(120% 92% at 44% 42%,#000 26%,transparent 76%);
}

.hero-inner{
  position:relative;
  width:100%;
  max-width:1080px;
  margin:0 auto;
  padding:3.25rem 1.25rem 3.75rem;
  display:grid;
  grid-template-columns:auto minmax(0,1fr);
  align-items:center;
  gap:2rem;
}

.hero-art-wrap{
  will-change:transform;
}

.hero-art{
  width:clamp(96px,16vw,170px);
  height:auto;
  border-radius:var(--r);
  border:1px solid var(--line);
  filter:grayscale(1) contrast(1.06);
  background:var(--panel);
}

.hero-seal{
  display:grid;
  place-items:center;
  width:clamp(88px,15vw,136px);
  height:clamp(88px,15vw,136px);
  border:1px solid var(--ink);
  border-radius:var(--r);
  background:var(--glass);
  backdrop-filter:blur(6px);
  font-family:var(--display);
  font-size:clamp(2rem,4.4vw,2.75rem);
  line-height:1;
}

.hero-copy{
  text-align:right;
  background:var(--glass);
  backdrop-filter:blur(8px) saturate(1.04);
  border:1px solid var(--line);
  border-radius:var(--r);
  padding:1.6rem 1.6rem 1.5rem;
}

h1{
  margin:0 0 .8rem;
  font-family:var(--display);
  font-weight:400;
  font-size:clamp(1.9rem,4.8vw,3.1rem);
  line-height:1.22;
  letter-spacing:-.01em;
  overflow-wrap:break-word;
}

.hero-desc{
  margin:0 0 0 auto;
  max-width:44ch;
  color:var(--soft);
  font-size:1.0625rem;
  line-height:1.7;
}

/* 主体 */
.wrap{
  max-width:1080px;
  margin:0 auto;
  padding:3rem 1.25rem 4.5rem;
}

.zone{
  display:grid;
  grid-template-columns:220px minmax(0,1fr);
  gap:2.5rem;
  align-items:start;
}

main [id]{scroll-margin-top:6.5rem}

/* 左侧栏 */
.toc{
  position:sticky;
  top:5.5rem;
  background:var(--glass);
  backdrop-filter:blur(8px);
  border:1px solid var(--line);
  border-radius:var(--r);
  padding:1rem 1.1rem 1.1rem;
}

.toc h2{
  margin:0 0 .45rem;
  font-family:var(--display);
  font-weight:400;
  font-size:1rem;
  letter-spacing:.24em;
  text-indent:.24em;
}

.toc hr{
  border-top:1px solid var(--line);
  width:auto;
  margin:.35rem 0 .7rem;
}

.toc ol{
  margin:0;
  padding:0;
  list-style:none;
  display:grid;
  gap:.1rem;
}

.toc a{
  display:block;
  padding:.55rem 0;
  font-size:1rem;
  line-height:1.5;
  text-decoration:none;
  border-bottom:1px dashed var(--line);
}

.toc li:last-child a{border-bottom:0}
.toc a:hover{text-decoration:underline;text-underline-offset:.3em}

/* 正文 */
.prose{
  min-width:0;
  max-width:70ch;
  overflow-wrap:break-word;
}

.prose > article{
  padding-top:2.75rem;
  margin-top:2.75rem;
  border-top:1px solid var(--line);
}

.prose > article:first-child{
  padding-top:0;
  margin-top:0;
  border-top:0;
}

.prose h2{
  margin:0 0 .5rem;
  font-family:var(--display);
  font-weight:400;
  font-size:clamp(1.4rem,2.7vw,1.85rem);
  line-height:1.32;
  letter-spacing:-.01em;
}

.prose h3{
  margin:1.9rem 0 .5rem;
  font-family:var(--display);
  font-weight:400;
  font-size:1.18rem;
  line-height:1.4;
}

.prose p{margin:0 0 1.1rem}
.prose ul,
.prose ol{margin:0 0 1.15rem;padding-left:1.35rem}
.prose li{margin:.42rem 0}
.prose li::marker{color:var(--soft)}

.prose blockquote{
  margin:1.4rem 0;
  padding:1rem 1.15rem;
  background:var(--glass);
  backdrop-filter:blur(6px);
  border:1px solid var(--line);
  border-left:3px solid var(--ink);
  border-radius:var(--r);
  color:#262421;
}

.prose blockquote > :last-child{margin-bottom:0}

.prose figure{
  margin:1.5rem 0;
  padding:.7rem;
  background:var(--glass);
  border:1px solid var(--line);
  border-radius:var(--r);
}

.prose figure img{border-radius:calc(var(--r) - 4px)}
.prose figcaption{margin-top:.55rem;font-size:1rem;color:var(--soft)}

.prose table{
  width:100%;
  border-collapse:collapse;
  margin:1.4rem 0;
  font-size:1rem;
}

.prose th,
.prose td{
  text-align:left;
  padding:.6rem .7rem;
  border-bottom:1px solid var(--line);
  vertical-align:top;
}

.prose th{
  border-bottom:2px solid var(--ink);
  font-family:var(--display);
  font-weight:400;
}

.prose code{
  font-family:var(--mono);
  font-size:.92em;
  background:var(--panel);
  border:1px solid var(--line);
  border-radius:4px;
  padding:.05em .35em;
}

.prose pre{
  overflow-x:auto;
  background:var(--panel);
  border:1px solid var(--line);
  border-radius:var(--r);
  padding:1rem;
}

.prose pre code{border:0;background:none;padding:0}

/* 页脚 */
.foot{
  border-top:1px solid var(--line);
  background:var(--panel);
  padding:2.5rem max(1.25rem,calc((100% - 1080px)/2)) 3rem;
  display:grid;
  grid-template-columns:minmax(0,1fr) minmax(0,1fr);
  gap:1.1rem 2.5rem;
  align-items:start;
}

.foot p{margin:0}

.foot-brand{
  font-size:1rem;
  line-height:1.7;
  color:var(--soft);
}

.foot-brand strong{
  display:inline-block;
  margin-bottom:.4rem;
  font-family:var(--display);
  font-weight:400;
  font-size:1.15rem;
  letter-spacing:.14em;
  color:var(--ink);
}

.foot-links{
  display:flex;
  flex-wrap:wrap;
  gap:.15rem .9rem;
  justify-content:flex-end;
}

.foot-links a{
  display:inline-flex;
  align-items:center;
  min-height:44px;
  font-size:1rem;
  text-decoration:none;
  border-bottom:1px solid transparent;
}

.foot-links a:hover{text-decoration:underline;text-underline-offset:.35em}

.foot-cta{
  grid-column:1 / -1;
  border-top:1px dashed var(--line);
  padding-top:1rem;
}

.foot-cta a{
  display:inline-flex;
  align-items:center;
  min-height:44px;
  font-size:1rem;
}

.foot-copy,
.foot-top{
  font-size:1rem;
  color:var(--soft);
  line-height:1.7;
}

.foot-top{justify-self:end}
.foot-top a{display:inline-flex;align-items:center;min-height:44px}

/* 动效 */
@media (prefers-reduced-motion: no-preference){
  .hero-copy > *,
  .toc li{
    animation:rise .32s ease-out both;
  }

  .hero-copy > *:nth-child(2){animation-delay:.05s}
  .toc li:nth-child(1){animation-delay:.04s}
  .toc li:nth-child(2){animation-delay:.07s}
  .toc li:nth-child(3){animation-delay:.1s}
  .toc li:nth-child(4){animation-delay:.13s}
  .toc li:nth-child(5){animation-delay:.16s}
  .toc li:nth-child(6){animation-delay:.19s}
  .toc li:nth-child(7){animation-delay:.22s}

  @keyframes rise{
    from{opacity:0;transform:translate3d(0,7px,0)}
    to{opacity:1;transform:none}
  }
}

@media (prefers-reduced-motion: reduce){
  html{scroll-behavior:auto}
  .hero-art-wrap{transform:none !important}
}

/* 窄屏 */
@media (max-width:46rem){
  body{font-size:17px}

  .mainnav{
    justify-content:center;
    padding:.15rem .75rem .4rem;
    gap:0 .3rem;
  }

  .brandmark{
    order:0;
    flex:1 0 100%;
    justify-content:center;
    border:0;
    border-bottom:1px solid var(--line);
    padding:.2rem 0;
  }

  .navlist > li,
  .navlist > li:nth-child(n+4){order:1}

  .navlist a{padding:0 .5rem}

  .hero{min-height:auto}

  .hero-inner{
    grid-template-columns:1fr;
    justify-items:start;
    gap:1.25rem;
    padding:2.25rem 1.1rem 2.75rem;
  }

  .hero-art,
  .hero-seal{
    width:74px;
    height:74px;
    font-size:2rem;
  }

  .hero-copy{
    text-align:left;
    padding:1.15rem 1.1rem 1.1rem;
    width:100%;
  }

  .hero-desc{max-width:none}

  .wrap{padding:2.25rem 1.1rem 3.25rem}

  .zone{grid-template-columns:minmax(0,1fr);gap:1.75rem}

  .toc{position:static;padding:.85rem 1rem 1rem}
  .toc ol{grid-template-columns:repeat(2,minmax(0,1fr));gap:0 1rem}
  .toc a{border-bottom:0;padding:.4rem 0}

  .prose{max-width:none}

  .foot{
    grid-template-columns:minmax(0,1fr);
    padding:2rem 1.1rem 2.5rem;
    gap:.75rem;
  }

  .foot-links{justify-content:flex-start}
  .foot-top{justify-self:start}
}

@media (max-width:24rem){
  .navlist a{padding:0 .35rem;font-size:.95rem}
}

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