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

:root{
  --ink:#000000;
  --paper:#ffffff;
  --hair:rgba(0,0,0,.14);
  --hair-2:rgba(0,0,0,.3);
  --mute:#3a3a3a;
  --u:8px;
  --bar:58px;
  --rail:46px;
  --pad:clamp(16px,4vw,52px);
  --r:28px;
  --shadow:0 22px 44px -30px rgba(0,0,0,.55);
  --sans:'Inter',-apple-system,BlinkMacSystemFont,'Helvetica Neue',Helvetica,Arial,'Noto Sans SC','PingFang SC','Microsoft YaHei',sans-serif;
  --display:'Playfair Display',Georgia,'Songti SC',serif;
}

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

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

body{
  margin:0;
  background:var(--paper);
  color:var(--ink);
  font-family:var(--sans);
  font-size:16px;
  line-height:1.7;
  font-weight:400;
  letter-spacing:.008em;
  overflow-x:hidden;
}

img{max-width:100%;height:auto;display:block}
a{color:inherit}
p{margin:0 0 1em}
a,button{-webkit-tap-highlight-color:transparent}

:focus-visible{
  outline:2px solid var(--ink);
  outline-offset:3px;
}

::selection{background:var(--ink);color:var(--paper)}

.wrap{
  max-width:1240px;
  margin:0 auto;
  padding:0 var(--pad);
}

/* ---------- top bar ---------- */

.topbar{
  position:sticky;
  top:0;
  z-index:60;
  display:flex;
  align-items:center;
  gap:12px;
  min-height:var(--bar);
  padding:0 var(--pad);
  background:var(--paper);
  border-bottom:1px solid var(--ink);
}

.mark-box{
  display:grid;
  place-items:center;
  width:40px;
  height:40px;
  flex:0 0 40px;
  border:1px solid var(--ink);
  border-radius:2px;
  text-decoration:none;
  transition:background .22s ease;
}
.mark-box:hover{background:#000}
.mark-box:hover .mark-glyph{filter:invert(1)}
.mark-img{width:36px;height:36px;object-fit:contain}
.mark-glyph{
  width:18px;height:18px;
  background:var(--ink);
  background-image:linear-gradient(#fff,#fff),linear-gradient(#fff,#fff);
  background-size:100% 2px,2px 100%;
  background-position:center center;
  background-repeat:no-repeat;
}

.menu-btn{
  margin-left:auto;
  display:inline-flex;
  align-items:center;
  min-height:44px;
  padding:0 16px;
  font:500 16px/1 var(--sans);
  letter-spacing:.06em;
  color:var(--ink);
  background:var(--paper);
  border:1px solid var(--ink);
  border-radius:999px;
  cursor:pointer;
}

.site-nav{
  display:none;
  position:absolute;
  top:100%;
  left:0;
  right:0;
  background:var(--paper);
  border-bottom:1px solid var(--ink);
  box-shadow:0 20px 30px -24px rgba(0,0,0,.5);
}
.site-nav.open{display:block}

.nav-list{
  list-style:none;
  margin:0;
  padding:8px var(--pad) 20px;
}
.nav-list li + li{border-top:1px solid var(--hair)}
.nav-list a{
  display:flex;
  align-items:center;
  gap:12px;
  min-height:48px;
  padding:6px 2px;
  font-size:16px;
  text-decoration:none;
}
.nav-idx{
  font-size:12px;
  font-variant-numeric:tabular-nums;
  letter-spacing:.12em;
  color:var(--mute);
  min-width:22px;
}
.nav-name{border-bottom:1px solid transparent}
.nav-list a:hover .nav-name{border-bottom-color:var(--ink)}

@media (min-width:1100px){
  .menu-btn{display:none}
  .site-nav{
    display:block;
    position:static;
    margin-left:auto;
    border-bottom:0;
    box-shadow:none;
    background:transparent;
  }
  .nav-list{
    display:flex;
    align-items:center;
    gap:2px;
    padding:0;
  }
  .nav-list li + li{border-top:0}
  .nav-list a{
    min-height:44px;
    padding:6px 12px;
    font-size:16px;
  }
  .nav-idx{display:none}
}

/* ---------- secondary anchor rail ---------- */

.rail{
  position:sticky;
  top:var(--bar);
  z-index:50;
  background:var(--ink);
  color:var(--paper);
}
.rail-list{
  display:flex;
  list-style:none;
  margin:0;
  padding:0;
  overflow-x:auto;
  scrollbar-width:thin;
  max-width:1240px;
  margin:0 auto;
}
.rail-list li{flex:0 0 auto}
.rail-list a{
  display:flex;
  align-items:center;
  gap:8px;
  min-height:var(--rail);
  padding:0 14px;
  font-size:16px;
  line-height:1.2;
  color:var(--paper);
  text-decoration:none;
  white-space:nowrap;
  border-right:1px solid rgba(255,255,255,.28);
  transition:background .2s ease,color .2s ease;
}
.rail-list a:hover,
.rail-list a.is-active{background:var(--paper);color:var(--ink)}
.rail-idx{font-size:12px;letter-spacing:.12em;font-variant-numeric:tabular-nums;opacity:.7}

/* ---------- hero ---------- */

.hero{
  display:grid;
  grid-template-columns:repeat(12,1fr);
  gap:16px;
  align-items:end;
  padding:clamp(24px,5vh,52px) 0 clamp(20px,4vh,40px);
  border-bottom:1px solid var(--ink);
  background-image:radial-gradient(rgba(0,0,0,.17) 1px,transparent 1px);
  background-size:16px 16px;
  background-position:0 0;
}

.hero-copy{
  grid-column:1 / -1;
  align-self:center;
}

.hero-title{
  font-family:var(--display);
  font-weight:600;
  font-size:clamp(30px,8.5vw,58px);
  line-height:1.06;
  letter-spacing:-.02em;
  margin:0 0 16px;
  max-width:19ch;
}

.hero-lead{
  font-size:17px;
  line-height:1.7;
  color:var(--mute);
  max-width:44ch;
  margin:0;
}

.hero-art{
  grid-column:1 / -1;
  margin:20px 0 0;
  border-radius:var(--r);
  overflow:hidden;
  box-shadow:var(--shadow);
  background:#f2f2f2;
  height:clamp(180px,32vh,300px);
}
.hero-img{
  width:100%;
  height:100%;
  object-fit:cover;
  transform:scale(1.08);
  will-change:transform;
}

@media (min-width:820px){
  .hero{align-items:center;min-height:45vh}
  .hero-copy{grid-column:1 / span 7}
  .hero-art{grid-column:8 / span 5;margin:0;height:clamp(240px,45vh,420px)}
  .hero-title{font-size:clamp(38px,4.6vw,62px)}
}

/* ---------- content shell ---------- */

.content-shell{
  display:grid;
  grid-template-columns:repeat(12,1fr);
  gap:16px;
  padding:clamp(28px,5vh,56px) 0 clamp(40px,7vh,80px);
}

.side{
  grid-column:1 / -1;
  align-self:start;
}
.side-title{
  font-family:var(--display);
  font-size:20px;
  font-weight:600;
  letter-spacing:.02em;
  margin:0 0 2px;
}
.subtitle{
  font-size:16px;
  color:var(--mute);
  margin:0 0 12px;
  padding-bottom:12px;
  border-bottom:1px solid var(--ink);
}

.side-list{
  list-style:none;
  margin:0;
  padding:0;
  display:grid;
  grid-template-columns:repeat(2,minmax(0,1fr));
  gap:0 12px;
}
.side-list a{
  display:flex;
  gap:8px;
  align-items:baseline;
  min-height:44px;
  padding:8px 0;
  font-size:16px;
  text-decoration:none;
  border-bottom:1px solid var(--hair);
  transition:border-color .2s ease,transform .2s ease;
}
.side-list a:hover{border-bottom-color:var(--ink);transform:translateX(3px)}
.side-idx{
  font-size:12px;
  letter-spacing:.1em;
  font-variant-numeric:tabular-nums;
  color:var(--mute);
}
.side-name{border-bottom:1px solid transparent}

.to-top{
  display:inline-flex;
  align-items:center;
  margin-top:16px;
  min-height:44px;
  padding:0 18px;
  font-size:16px;
  text-decoration:none;
  border:1px solid var(--ink);
  border-radius:999px;
  transition:background .22s ease,color .22s ease;
}
.to-top:hover{background:var(--ink);color:var(--paper)}

.body{
  grid-column:1 / -1;
  min-width:0;
  background:var(--paper);
  border:1px solid var(--hair);
  border-radius:var(--r);
  box-shadow:var(--shadow);
  padding:clamp(20px,3.4vw,44px);
}

@media (min-width:820px){
  .side{
    grid-column:1 / span 3;
    position:sticky;
    top:calc(var(--bar) + var(--rail) + 24px);
  }
  .side-list{grid-template-columns:1fr}
  .body{grid-column:4 / span 9}
}

/* ---------- div body ---------- */

.body > *:first-child{margin-top:0}
.body > *:last-child{margin-bottom:0}

.body article[id]{scroll-margin-top:calc(var(--bar) + var(--rail) + 20px)}
.body article + article{
  margin-top:clamp(32px,5vh,56px);
  padding-top:clamp(24px,4vh,40px);
  border-top:1px solid var(--ink);
}

.body h2{
  font-family:var(--display);
  font-weight:600;
  font-size:clamp(23px,3.1vw,34px);
  line-height:1.2;
  letter-spacing:-.01em;
  margin:0 0 14px;
}

.body h2 + p{
  font-size:17px;
  color:var(--mute);
  margin-top:-4px;
}

.body h3{
  font-family:var(--sans);
  font-weight:600;
  font-size:19px;
  line-height:1.4;
  margin:28px 0 10px;
}

.body p{margin:0 0 1.05em}
.body ul,.body ol{margin:0 0 1.1em;padding-left:1.25em}
.body li{margin:0 0 .5em}
.body li::marker{color:var(--mute)}

.body a{
  text-decoration:underline;
  text-decoration-thickness:1px;
  text-underline-offset:3px;
}
.body a:hover{background:var(--ink);color:var(--paper);text-decoration-color:transparent}

.body img{border-radius:18px;margin:20px 0}
.body figure{margin:20px 0}
.body figcaption{font-size:16px;color:var(--mute);margin-top:8px}

.body blockquote{
  margin:20px 0;
  padding:4px 0 4px 20px;
  border-left:3px solid var(--ink);
  font-family:var(--display);
  font-size:19px;
  line-height:1.6;
}

.body code{
  font-family:ui-monospace,SFMono-Regular,Menlo,monospace;
  font-size:15px;
  background:#f1f1f1;
  padding:1px 5px;
  border-radius:4px;
}

.body table{
  width:100%;
  border-collapse:collapse;
  margin:20px 0;
  font-size:16px;
}
.body th,.body td{
  border-bottom:1px solid var(--hair);
  padding:10px 8px;
  text-align:left;
}

/* ---------- footer ---------- */

.foot{
  background:var(--ink);
  color:var(--paper);
  padding:clamp(32px,6vh,64px) var(--pad) 20px;
}

.cta{
  max-width:1240px;
  margin:0 auto;
  display:flex;
  flex-wrap:wrap;
  align-items:baseline;
  justify-content:space-between;
  gap:20px;
  padding-bottom:32px;
  border-bottom:1px solid rgba(255,255,255,.35);
}

.cta-text{
  font-family:var(--display);
  font-size:clamp(30px,7vw,68px);
  line-height:1;
  letter-spacing:-.02em;
  margin:0;
}

.cta-link{
  display:inline-flex;
  align-items:center;
  min-height:46px;
  padding:0 22px;
  font-size:16px;
  color:var(--paper);
  text-decoration:none;
  border:1px solid var(--paper);
  border-radius:999px;
  transition:background .22s ease,color .22s ease;
}
.cta-link:hover{background:var(--paper);color:var(--ink)}

.foot-row{
  max-width:1240px;
  margin:0 auto;
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:10px 18px;
  padding-top:20px;
}

.foot-mark{
  display:grid;
  place-items:center;
  width:40px;
  height:40px;
  flex:0 0 40px;
  border:1px solid var(--paper);
  border-radius:2px;
  text-decoration:none;
}
.foot-mark .mark-glyph{background:var(--paper);background-image:linear-gradient(#000,#000),linear-gradient(#000,#000)}
.foot-mark .mark-img{filter:invert(1)}

.foot-nav{flex:1 1 auto}
.foot-dl{
  display:flex;
  flex-wrap:wrap;
  margin:0;
  padding:0;
}
.foot-dl dt{margin:0}
.foot-dl dd{margin:0}
.foot-dl a{
  display:inline-flex;
  align-items:center;
  min-height:44px;
  padding:0 12px;
  font-size:16px;
  color:var(--paper);
  text-decoration:none;
  border-bottom:1px solid transparent;
  transition:border-color .2s ease;
}
.foot-dl a:hover{border-bottom-color:var(--paper)}

.copy{
  margin:0 0 0 auto;
  font-size:16px;
  color:rgba(255,255,255,.72);
}

@media (max-width:700px){
  .copy{margin:0;flex:0 0 100%}
  .foot-dl a{padding:0 10px 0 0}
}

/* ---------- motion ---------- */

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{transition-duration:.001ms !important;animation-duration:.001ms !important}
  .hero-img{transform:none !important}
}

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