:root {
  --paper: #f4f1e9;
  --card: #fbf9f3;
  --ink: #423e33;
  --mute: #686252;
  --red: #924c3a;
  --line: rgba(76, 65, 43, .16);
  --serif: "Songti SC", "STSong", "Noto Serif CJK SC", "Noto Serif SC", Georgia, serif;
  --kai: "Kaiti SC", "STKaiti", "KaiTi", var(--serif);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--paper); color: var(--ink); font: 16px/1.8 var(--serif); }
a { color: inherit; }
img { display: block; max-width: 100%; height: auto; }

.bar {
  position: sticky; top: 0; z-index: 5;
  display: flex; justify-content: space-between; align-items: center; gap: 16px;
  max-width: 1120px; margin: 0 auto; padding: 18px 24px;
  background: color-mix(in srgb, var(--paper) 92%, transparent);
  backdrop-filter: blur(6px);
  border-bottom: 1px solid var(--line);
}
.wordmark { display: flex; align-items: center; gap: 12px; text-decoration: none; }
.wordmark img { width: 150px; height: auto; flex: 0 0 auto; }
.wordmark small { font-size: 12px; color: var(--mute); letter-spacing: .12em; }
nav { display: flex; gap: 22px; font-size: 14px; letter-spacing: .12em; }
nav a { text-decoration: none; border-bottom: 1px solid transparent; }
nav a:hover { border-color: var(--red); color: var(--red); }

main { max-width: 1120px; margin: 0 auto; padding: 0 24px; }

.hero {
  padding: 96px 0 72px; border-bottom: 1px solid var(--line);
  background: linear-gradient(to right, var(--paper) 0%, rgba(244, 241, 233, .94) 45%, rgba(244, 241, 233, .3) 100%), url("brand/bg-heritage.jpg") right bottom / cover no-repeat;
}
.eyebrow { margin: 0 0 20px; font: 12px/1 Georgia, serif; letter-spacing: .28em; color: var(--mute); }
.motto { margin: 0 0 18px; color: var(--red); font: 500 18px/1.6 var(--kai); letter-spacing: .2em; }
.hero h1 { margin: 0; font: 500 clamp(32px, 5.4vw, 60px)/1.35 var(--serif); letter-spacing: .04em; }
.lede { max-width: 36em; margin: 28px 0 0; font-size: 17px; color: var(--mute); }

.block { padding: 64px 0; border-bottom: 1px solid var(--line); }
.block h2 { display: flex; align-items: baseline; gap: 14px; margin: 0 0 32px; font: 500 24px/1.2 var(--serif); letter-spacing: .2em; }
.block h2 span { font: 12px/1 Georgia, serif; letter-spacing: .1em; color: var(--red); }
.note { max-width: 40em; margin: -12px 0 28px; color: var(--mute); }

.entry { display: grid; grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr); gap: 40px; align-items: center; background: var(--card); border: 1px solid var(--line); padding: 24px; }
.entry-text { padding: 8px 8px 8px 0; }
.no { margin: 0; font-size: 13px; letter-spacing: .14em; color: var(--mute); }
.entry h3 { margin: 6px 0 18px; font: 500 40px/1.2 var(--kai); letter-spacing: .3em; }
.facts { margin: 0; }
.facts div { display: grid; grid-template-columns: 3.5em 1fr; gap: 8px; padding: 7px 0; border-top: 1px solid var(--line); font-size: 15px; }
.facts dt { color: var(--mute); }
.facts dd { margin: 0; }
.status { margin: 18px 0 0; padding-left: 12px; border-left: 2px solid var(--red); color: var(--red); font-size: 14px; }
.go { display: inline-block; margin-top: 22px; padding: 10px 22px; background: var(--red); color: #fff; text-decoration: none; letter-spacing: .14em; font-size: 15px; }
.go:hover { background: #7a3d2e; }

.compare { position: relative; aspect-ratio: 625 / 590; overflow: hidden; background: #f7f5ee; touch-action: pan-y; cursor: ew-resize; user-select: none; -webkit-user-select: none; }
.compare img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; pointer-events: none; -webkit-user-drag: none; }
.compare .after { clip-path: inset(0 0 0 var(--cut)); }
.compare::after { content: ""; position: absolute; top: 0; bottom: 0; left: var(--cut); width: 2px; margin-left: -1px; background: var(--red); pointer-events: none; }
.handle { position: absolute; top: 84%; left: var(--cut); width: 44px; height: 44px; margin: -22px 0 0 -22px; border-radius: 50%; background: var(--red); box-shadow: 0 2px 8px rgba(66, 62, 51, .3); pointer-events: none; }
.handle::before { content: "‹ ›"; position: absolute; inset: 0; display: grid; place-items: center; color: #fff; font: 20px/1 Georgia, serif; letter-spacing: .1em; }
.compare input { position: absolute; width: 1px; height: 1px; opacity: 0; pointer-events: none; }
.compare:has(input:focus-visible) { outline: 2px solid var(--red); outline-offset: 3px; }
.tag { position: absolute; top: 12px; padding: 3px 10px; font-size: 12px; letter-spacing: .1em; background: rgba(251, 249, 243, .9); border: 1px solid var(--line); pointer-events: none; }
.tag.l { left: 12px; }
.tag.r { right: 12px; color: var(--red); }

.entry.next { display: flex; flex-direction: column; gap: 6px; margin-top: 20px; padding: 28px; background: none; border-style: dashed; text-decoration: none; }
.entry.next b { font: 500 22px/1.4 var(--kai); letter-spacing: .1em; }
.entry.next span:last-child { color: var(--red); font-size: 14px; }
.entry.next:hover { border-color: var(--red); }

.studies { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 20px; }
.study { display: flex; flex-direction: column; gap: 4px; padding: 14px 14px 18px; background: var(--card); border: 1px solid var(--line); text-decoration: none; }
.study img { aspect-ratio: 625 / 590; object-fit: cover; margin-bottom: 10px; }
.study b { font: 500 18px/1.4 var(--serif); letter-spacing: .14em; }
.study span { font-size: 13px; color: var(--mute); line-height: 1.6; }
.study:hover { border-color: var(--red); }

.rules { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 28px; margin: 0; padding: 0; list-style: none; counter-reset: r; }
.rules li { counter-increment: r; padding-top: 16px; border-top: 2px solid var(--ink); color: var(--mute); font-size: 15px; }
.rules b { display: block; margin-bottom: 8px; color: var(--ink); font: 500 20px/1.4 var(--kai); letter-spacing: .14em; }
.rules b::before { content: counter(r, cjk-ideographic) "、"; color: var(--red); }

.clue p { max-width: 40em; margin: 0; }
.actions { display: flex; gap: 14px; margin-top: 24px !important; }
.btn { padding: 10px 24px; background: var(--ink); color: var(--paper); text-decoration: none; letter-spacing: .14em; font-size: 15px; }
.btn.ghost { background: none; color: var(--ink); border: 1px solid var(--ink); }
.btn:hover { background: var(--red); border-color: var(--red); color: #fff; }
.small { margin-top: 12px !important; font-size: 13px; color: var(--mute); }

.form { display: grid; gap: 16px; max-width: 40em; margin-top: 28px; }
.form fieldset { display: grid; gap: 16px; min-width: 0; margin: 0; padding: 0; border: 0; }
.form fieldset[hidden] { display: none; }
.seg { display: inline-flex; width: max-content; border: 1px solid var(--ink); }
.seg label { padding: 8px 22px; font-size: 15px; letter-spacing: .14em; cursor: pointer; }
.seg input { position: absolute; opacity: 0; pointer-events: none; }
.seg label:has(input:checked) { background: var(--ink); color: var(--paper); }
.seg label:has(input:focus-visible) { outline: 2px solid var(--red); outline-offset: 2px; }
.f { display: grid; gap: 6px; font-size: 15px; }
.f em { margin-left: 10px; font-style: normal; font-size: 13px; color: var(--mute); }
.f input, .f textarea { width: 100%; padding: 10px 12px; font: 16px/1.6 var(--serif); color: var(--ink); background: var(--card); border: 1px solid var(--line); border-radius: 0; }
.f input:focus, .f textarea:focus { outline: 2px solid var(--red); outline-offset: -2px; }
.f input[type="file"] { padding: 8px; font-size: 14px; }
.row2 { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.form .actions { margin-top: 0 !important; }
button.btn { border: 0; font-family: inherit; cursor: pointer; }
button.btn:disabled { opacity: .5; cursor: wait; }
.form .status { margin: 0; padding: 0; border: 0; font-size: 14px; }
.form .status:empty { display: none; }
.done { padding: 20px 24px; background: var(--card); border: 1px solid var(--line); }

footer { max-width: 1120px; margin: 0 auto; padding: 32px 24px 48px; font-size: 13px; color: var(--mute); }
footer p { margin: 0 0 4px; }

@media (max-width: 760px) {
  .bar { padding: 12px 16px; }
  .wordmark small { display: none; }
  .wordmark img { width: 124px; }
  nav { gap: 14px; font-size: 13px; }
  main { padding: 0 16px; }
  .hero {
    padding: 56px 0 44px;
    background-image: linear-gradient(to right, rgba(244, 241, 233, .96), rgba(244, 241, 233, .8)), url("brand/bg-heritage.jpg");
  }
  .hero h1 { font-size: 28px; }
  .block { padding: 44px 0; }
  .entry { grid-template-columns: 1fr; gap: 20px; padding: 14px; }
  .entry-text { padding: 0 4px 6px; }
  .entry h3 { font-size: 32px; }
  .studies, .rules, .row2 { grid-template-columns: 1fr; }
  footer { padding: 28px 16px 40px; }
}

@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }