/* Design tokens */
:root{
  --ink:#142b35;
  --muted:#5d6f74;
  --paper:#f6f9f7;
  --white:#fff;
  --card:#fff;
  --blue:#23698b;
  --cyan:#bde7e3;
  --cyan-faint:#e7f5f3;
  --line:#cbd8d8;
  --line-light:#e5edec;
  --rust:#a9472d;
  --rust-faint:#f4e4df;
  --display:"Shippori Mincho", "Hiragino Mincho ProN", "Yu Mincho", serif;
  --body:"BIZ UDGothic", "Hiragino Kaku Gothic ProN", "Yu Gothic", sans-serif;
  --mono:"IBM Plex Mono", "BIZ UDGothic", monospace;
  --max:1180px;
  --radius:2px;
  --shadow-card:0 1px 2px rgba(20,43,53,0.06), 0 2px 6px rgba(20,43,53,0.04);
}

/* Reset & base */
*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}}
body{
  margin:0;
  color:var(--ink);
  background:var(--paper);
  font-family:var(--body);
  line-height:1.75;
  font-size:15px;
  -webkit-text-size-adjust:100%;
}
a{color:inherit;text-underline-offset:.22em}
a:hover{text-decoration-thickness:2px}
img{max-width:100%;height:auto}
button,input,textarea,select{font:inherit}

/* Focus */
.skip{
  position:absolute;
  left:1rem;
  top:-5rem;
  background:var(--ink);
  color:var(--white);
  padding:.7rem 1rem;
  z-index:100;
  border-radius:var(--radius);
  text-decoration:none;
}
.skip:focus{top:1rem}
:focus-visible{
  outline:3px solid var(--rust);
  outline-offset:3px;
}
button:focus-visible,a:focus-visible,input:focus-visible,textarea:focus-visible,select:focus-visible{
  border-radius:var(--radius);
}

/* Header */
.site-header{
  position:sticky;
  top:0;
  z-index:40;
  height:72px;
  padding:0 max(20px,calc((100vw - var(--max))/2));
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:16px;
  border-bottom:1px solid var(--line);
  background:rgba(246,249,247,0.96);
  backdrop-filter:blur(4px);
}
.brand{
  display:flex;
  align-items:center;
  gap:10px;
  text-decoration:none;
  font-weight:700;
  line-height:1.2;
}
.brand-mark{
  display:grid;
  place-items:center;
  width:38px;
  height:38px;
  border:1.5px solid var(--ink);
  font-family:var(--display);
  font-size:20px;
  border-radius:var(--radius);
  flex:none;
}
.brand-text{display:flex;flex-direction:column;gap:2px}
.brand-title{font-size:15px;letter-spacing:-0.02em}
.brand-sub{display:block;font:600 9px/1.4 var(--mono);letter-spacing:0.1em;color:var(--blue)}
.site-header nav{display:flex;gap:22px;flex-wrap:wrap}
.site-header nav a{
  text-decoration:none;
  font-size:13.5px;
  font-weight:700;
  color:var(--ink);
  padding:4px 2px;
}
.site-header nav a:hover{color:var(--blue)}

/* Typography helpers */
.eyebrow{
  font:600 11px/1.5 var(--mono);
  letter-spacing:0.14em;
  color:var(--blue);
  text-transform:uppercase;
  margin:0 0 0.6rem;
}
.section-wrap{
  max-width:var(--max);
  margin:0 auto;
  padding:56px max(20px,calc((100vw - var(--max))/2));
}
.section-head{
  display:flex;
  align-items:flex-end;
  justify-content:space-between;
  gap:20px;
  margin-bottom:28px;
  flex-wrap:wrap;
}
.section-head h2{font-family:var(--display);font-size:28px;font-weight:600;margin:0}
.section-head a{font-size:13px;font-weight:700;color:var(--blue)}

/* Hero */
.hero{
  max-width:var(--max);
  margin:0 auto;
  display:grid;
  grid-template-columns:1.4fr .75fr;
  gap:6vw;
  align-items:center;
  padding:64px max(20px,calc((100vw - var(--max))/2)) 80px;
  border-bottom:1px solid var(--line);
}
.hero h1{
  font-family:var(--display);
  font-size:clamp(38px,6.2vw,72px);
  font-weight:600;
  line-height:1.18;
  letter-spacing:-0.04em;
  margin:0.2em 0 0.35em;
}
.hero h1 em{
  font-style:normal;
  background:linear-gradient(transparent 66%, var(--cyan) 66%);
}
.hero .lead{
  max-width:640px;
  font-size:16px;
  color:#304851;
  line-height:1.85;
}
.hero-actions{display:flex;align-items:center;gap:18px;margin-top:30px;flex-wrap:wrap}

/* Buttons */
.button{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:8px;
  min-height:44px;
  padding:0.65em 1.4em;
  background:var(--ink);
  color:var(--white);
  border:1.5px solid var(--ink);
  border-radius:var(--radius);
  text-decoration:none;
  font-weight:700;
  font-size:14px;
  cursor:pointer;
  line-height:1.3;
}
.button:hover{background:var(--white);color:var(--ink)}
.button.inverse{background:var(--white);color:var(--ink)}
.button.inverse:hover{background:var(--ink);color:var(--white)}
.button.full{width:100%}
.button.secondary{
  background:transparent;
  color:var(--ink);
  border-color:var(--line);
}
.button.secondary:hover{border-color:var(--ink)}
.sub-action{font-size:14px;font-weight:700;color:var(--blue);text-decoration:underline}

/* Register sheet (hero aside) */
.register-sheet{
  border:1px solid var(--line);
  background:var(--card);
  padding:26px 24px 24px;
  box-shadow:var(--shadow-card);
  border-radius:var(--radius);
}
.sheet-stamp{
  display:inline-block;
  border:2px solid var(--ink);
  padding:10px 14px;
  font-family:var(--mono);
  font-weight:700;
  font-size:15px;
  letter-spacing:0.06em;
  line-height:1.3;
  margin-bottom:18px;
}
.register-sheet p{margin:0 0 6px;color:var(--muted);font-size:13px}
.register-sheet strong{font-family:var(--display);font-size:42px;font-weight:600;color:var(--ink)}
.register-sheet strong small{font-size:18px;margin-left:2px;font-family:var(--body)}
.register-sheet ul{
  list-style:none;
  margin:18px 0 0;
  padding:12px 0 0;
  border-top:1px solid var(--line-light);
  font-size:13.5px;
  display:grid;
  gap:6px;
}
.register-sheet li{display:flex;justify-content:space-between;gap:10px}
.register-sheet li b{font-weight:700;color:var(--blue)}
.sheet-note{
  margin-top:16px;
  padding-top:12px;
  border-top:1px solid var(--line-light);
  font-size:12.5px;
  color:var(--muted);
  line-height:1.65;
}

/* Principles */
.principles{
  max-width:var(--max);
  margin:0 auto;
  padding:56px max(20px,calc((100vw - var(--max))/2));
  display:grid;
  grid-template-columns:repeat(3,1fr);
  gap:28px;
}
.principles > div{
  border-top:3px solid var(--cyan);
  padding-top:18px;
}
.principles span{
  display:block;
  font-family:var(--mono);
  font-size:12px;
  font-weight:700;
  color:var(--blue);
  margin-bottom:8px;
}
.principles h2{
  font-family:var(--display);
  font-size:21px;
  font-weight:600;
  line-height:1.3;
  margin:0 0 10px;
}
.principles p{font-size:14px;color:var(--muted);line-height:1.75;margin:0}

/* Card grid */
.card-grid{
  display:grid;
  grid-template-columns:repeat(auto-fill,minmax(300px,1fr));
  gap:22px;
}
.source-card{
  border:1px solid var(--line);
  background:var(--card);
  border-radius:var(--radius);
  padding:22px 22px 20px;
  display:flex;
  flex-direction:column;
  gap:12px;
  box-shadow:var(--shadow-card);
}
.source-card .card-meta{
  display:flex;
  gap:8px;
  flex-wrap:wrap;
}
.source-card .card-meta span{
  font:600 11px/1.4 var(--mono);
  letter-spacing:0.04em;
  color:var(--blue);
  background:var(--cyan-faint);
  padding:3px 8px;
  border-radius:var(--radius);
}
.source-card h2{
  font-family:var(--display);
  font-size:20px;
  font-weight:600;
  line-height:1.35;
  margin:0;
}
.source-card h2 a{text-decoration:none}
.source-card h2 a:hover{text-decoration:underline}
.source-card > p{font-size:14px;color:var(--muted);line-height:1.7;margin:0}
.source-card dl{
  margin:0;
  display:grid;
  gap:6px;
  font-size:13px;
}
.source-card dl div{display:grid;grid-template-columns:6.5em 1fr;gap:8px}
.source-card dt{color:var(--muted);font-weight:400}
.source-card dd{margin:0;font-weight:600}
.source-card .text-link{
  margin-top:auto;
  padding-top:14px;
  font-size:13.5px;
  font-weight:700;
  color:var(--blue);
  text-decoration:none;
}
.source-card .text-link:hover{text-decoration:underline}

/* Page intro */
.page-intro{
  max-width:var(--max);
  margin:0 auto;
  padding:52px max(20px,calc((100vw - var(--max))/2)) 40px;
  text-align:center;
}
.page-intro.left{text-align:left}
.page-intro h1{
  font-family:var(--display);
  font-size:clamp(32px,5vw,52px);
  font-weight:600;
  line-height:1.2;
  letter-spacing:-0.03em;
  margin:0.2em 0 0.5em;
}
.page-intro > p{
  max-width:680px;
  margin:0 auto 26px;
  color:var(--muted);
  font-size:15.5px;
  line-height:1.8;
}
.page-intro.left > p{margin-left:0}
.page-intro .hero-actions{justify-content:center;margin-top:0}
.page-intro.left .hero-actions{justify-content:flex-start}

/* Catalog filters */
.catalog{padding-top:0}
.filter-bar{
  display:flex;
  flex-wrap:wrap;
  gap:8px;
  align-items:center;
  padding:16px 0;
  border-top:1px solid var(--line);
  border-bottom:1px solid var(--line);
  margin-bottom:18px;
}
.filter-bar label{
  font-size:13px;
  font-weight:700;
  color:var(--muted);
  margin-right:6px;
}
.filter{
  display:inline-flex;
  align-items:center;
  gap:6px;
  min-height:36px;
  padding:0.4em 0.85em;
  background:var(--white);
  border:1px solid var(--line);
  border-radius:var(--radius);
  color:var(--ink);
  font-size:13px;
  font-weight:700;
  cursor:pointer;
}
.filter:hover{border-color:var(--blue)}
.filter.active{
  background:var(--ink);
  color:var(--white);
  border-color:var(--ink);
}
.filter span{font-family:var(--mono);font-size:11px;opacity:0.8}

/* Search */
.search-row{
  display:flex;
  gap:12px;
  flex-wrap:wrap;
  margin-bottom:18px;
}
.search-input{
  flex:1 1 240px;
  min-height:44px;
  padding:0.55em 0.9em;
  border:1px solid var(--line);
  border-radius:var(--radius);
  background:var(--white);
  color:var(--ink);
  font-size:14px;
}
.search-input:focus{border-color:var(--blue);box-shadow:0 0 0 3px var(--cyan-faint)}

/* Result status */
.result-status{
  font-size:13.5px;
  color:var(--muted);
  margin:0 0 14px;
}
.result-status strong{color:var(--ink)}

/* Empty / error states */
.empty-state,
.error-state{
  border:1px dashed var(--line);
  background:var(--white);
  padding:40px 24px;
  text-align:center;
  border-radius:var(--radius);
}
.empty-state p,
.error-state p{max-width:520px;margin:0 auto 18px;color:var(--muted)}
.empty-state h2,
.error-state h2{font-family:var(--display);font-size:24px;margin:0 0 10px}
.error-state{border-color:var(--rust);background:var(--rust-faint)}
.error-state h2{color:var(--rust)}

/* Record / source detail */
.record{padding-top:40px}
.record header{margin-bottom:32px}
.back-link{
  display:inline-flex;
  align-items:center;
  gap:6px;
  font-size:13px;
  font-weight:700;
  color:var(--blue);
  text-decoration:none;
  margin-bottom:14px;
}
.back-link:hover{text-decoration:underline}
.record-id{
  font-family:var(--mono);
  font-size:12px;
  color:var(--muted);
  letter-spacing:0.06em;
  margin-bottom:10px;
}
.record h1{
  font-family:var(--display);
  font-size:clamp(30px,4.5vw,46px);
  font-weight:600;
  line-height:1.2;
  letter-spacing:-0.02em;
  margin:0 0 12px;
}
.publisher{font-size:15px;color:var(--muted);margin:0}
.publisher strong{color:var(--ink)}
.record-layout{
  display:grid;
  grid-template-columns:1fr 320px;
  gap:44px;
  align-items:start;
}
.record-main{display:grid;gap:36px}
.record-main section h2{
  font-family:var(--display);
  font-size:22px;
  font-weight:600;
  margin:0 0 12px;
  padding-bottom:8px;
  border-bottom:1px solid var(--line-light);
}
.record-main p{margin:0 0 12px;color:#304851}
.record-main ol,
.record-main ul{margin:0;padding-left:1.5em;color:#304851}
.record-main li{margin-bottom:6px}
.caveat{
  border-left:4px solid var(--rust);
  background:var(--rust-faint);
  padding:16px 18px;
  border-radius:0 var(--radius) var(--radius) 0;
}
.caveat strong{
  display:block;
  font-size:13px;
  color:var(--rust);
  margin-bottom:6px;
  letter-spacing:0.04em;
}
.caveat p{margin:0;color:var(--ink)}

/* Facts sidebar */
.facts{
  position:sticky;
  top:90px;
  border:1px solid var(--line);
  background:var(--card);
  border-radius:var(--radius);
  padding:22px;
  box-shadow:var(--shadow-card);
}
.facts h2{
  font-family:var(--display);
  font-size:18px;
  font-weight:600;
  margin:0 0 16px;
  padding-bottom:10px;
  border-bottom:1px solid var(--line-light);
}
.facts dl{margin:0;display:grid;gap:10px}
.facts dl div{display:grid;grid-template-columns:6em 1fr;gap:10px;font-size:13.5px}
.facts dt{color:var(--muted);font-weight:400}
.facts dd{margin:0;font-weight:600;word-break:break-word}
.facts .button{margin-top:20px}

/* Methodology / prose pages */
.prose{padding-top:40px}
.prose h2{
  font-family:var(--display);
  font-size:24px;
  font-weight:600;
  margin:44px 0 14px;
  padding-bottom:8px;
  border-bottom:1px solid var(--line-light);
}
.prose h2:first-of-type{margin-top:0}
.prose p{color:#304851;margin:0 0 14px}
.prose ol.protocol{
  list-style:none;
  margin:0;
  padding:0;
  display:grid;
  gap:16px;
  counter-reset:protocol;
}
.prose ol.protocol li{
  display:grid;
  grid-template-columns:2.2em 1fr;
  gap:14px;
  align-items:start;
  padding:16px 18px;
  border:1px solid var(--line-light);
  background:var(--white);
  border-radius:var(--radius);
}
.prose ol.protocol li::before{
  counter-increment:protocol;
  content:counter(protocol, decimal-leading-zero);
  font-family:var(--mono);
  font-weight:700;
  color:var(--blue);
  line-height:1.4;
}
.prose ol.protocol strong{display:block;margin-bottom:4px}
.prose ol.protocol span{color:var(--muted);font-size:14px}
.prose pre{
  background:var(--white);
  border:1px solid var(--line-light);
  padding:16px;
  border-radius:var(--radius);
  overflow:auto;
  font-size:13.5px;
}
.prose pre code{font-family:var(--mono)}

/* Citation callout */
.citation-callout{
  max-width:var(--max);
  margin:0 auto 64px;
  padding:44px max(20px,calc((100vw - var(--max))/2));
  border-top:1px solid var(--line);
  border-bottom:1px solid var(--line);
  background:var(--cyan-faint);
}
.citation-callout h2{
  font-family:var(--display);
  font-size:26px;
  font-weight:600;
  line-height:1.3;
  margin:0 0 12px;
}
.citation-callout p{max-width:700px;color:#304851;margin:0 0 20px}

/* Correction form */
.form-page{
  display:grid;
  grid-template-columns:1fr 1.1fr;
  gap:56px;
  align-items:start;
}
.form-page h1{
  font-family:var(--display);
  font-size:clamp(30px,4.5vw,46px);
  font-weight:600;
  margin:0 0 16px;
}
.form-page > div > p{color:var(--muted);margin:0 0 16px}
.quiet-list{
  list-style:none;
  margin:0 0 24px;
  padding:0;
  display:grid;
  gap:8px;
}
.quiet-list li{
  padding-left:22px;
  position:relative;
  font-size:14px;
  color:#304851;
}
.quiet-list li::before{
  content:"";
  position:absolute;
  left:0;
  top:8px;
  width:10px;
  height:10px;
  border:2px solid var(--blue);
  border-radius:50%;
}
.correction-form{
  border:1px solid var(--line);
  background:var(--card);
  border-radius:var(--radius);
  padding:28px;
  box-shadow:var(--shadow-card);
  display:grid;
  gap:18px;
}
.correction-form label{
  display:grid;
  gap:6px;
  font-size:13.5px;
  font-weight:700;
}
.correction-form input,
.correction-form textarea{
  width:100%;
  padding:0.6em 0.8em;
  border:1px solid var(--line);
  border-radius:var(--radius);
  background:var(--white);
  color:var(--ink);
  font-weight:400;
}
.correction-form input:focus,
.correction-form textarea:focus{
  border-color:var(--blue);
  box-shadow:0 0 0 3px var(--cyan-faint);
}
.correction-form small{font-weight:400;color:var(--muted);font-size:12.5px}
.correction-form .success{
  background:var(--cyan-faint);
  border:1px solid var(--cyan);
  padding:12px 14px;
  border-radius:var(--radius);
  color:var(--ink);
  font-weight:700;
  margin:0;
}
.form-note{font-size:12.5px;color:var(--muted);margin:0;line-height:1.65}

/* Not found */
.not-found{
  max-width:var(--max);
  margin:0 auto;
  padding:90px max(20px,calc((100vw - var(--max))/2));
  text-align:center;
}
.not-found h1{
  font-family:var(--display);
  font-size:clamp(32px,5vw,52px);
  font-weight:600;
  margin:0 0 16px;
}
.not-found p{color:var(--muted);margin:0 0 28px}

/* Footer */
footer{
  max-width:var(--max);
  margin:0 auto;
  padding:44px max(20px,calc((100vw - var(--max))/2)) 56px;
  border-top:1px solid var(--line);
  display:grid;
  grid-template-columns:1fr auto;
  gap:28px;
}
footer strong{font-family:var(--display);font-size:18px}
footer p{color:var(--muted);font-size:13.5px;margin:8px 0 0;max-width:420px;line-height:1.7}
footer nav{display:flex;gap:20px;flex-wrap:wrap}
footer nav a{font-size:13.5px;font-weight:700;color:var(--blue);text-decoration:none}
footer nav a:hover{text-decoration:underline}
.operator{
  grid-column:1 / -1;
  font-size:12.5px;
  color:var(--muted);
  margin:8px 0 0;
  padding-top:14px;
  border-top:1px solid var(--line-light);
}

/* Screen reader only */
.sr-only{
  position:absolute;
  width:1px;
  height:1px;
  padding:0;
  margin:-1px;
  overflow:hidden;
  clip:rect(0,0,0,0);
  white-space:nowrap;
  border:0;
}

/* Mobile */
@media (max-width:900px){
  .hero{grid-template-columns:1fr}
  .register-sheet{max-width:360px}
  .principles{grid-template-columns:1fr}
  .record-layout{grid-template-columns:1fr}
  .facts{position:static}
  .form-page{grid-template-columns:1fr}
}

@media (max-width:640px){
  .site-header{height:auto;min-height:64px;padding:12px 16px;flex-wrap:wrap}
  .brand-sub{display:none}
  .site-header nav{gap:14px}
  .site-header nav a{font-size:12.5px}
  .hero{padding:40px 16px 56px}
  .section-wrap{padding:40px 16px}
  .card-grid{grid-template-columns:1fr}
  .principles{gap:30px}
  .page-intro{padding:36px 16px 28px}
  .citation-callout{padding:32px 16px}
  .not-found{padding:64px 16px}
  footer{grid-template-columns:1fr}
}