/* ARKEIN · Human Reader v1.4 · responsive typography balance · E-Ink Reader v0.2 + Brand Identity v1 */
:root {
  color-scheme:light;
  --outer:#d9ded8;--paper:#e9ece6;--ink:#262824;--text:#303832;
  --secondary:#4e5a51;--muted:#66736a;--line:#c8d0c7;--soft:#e0e5dd;
  --accent:#33483c;--focus:#435b4c;--shade:rgba(32,41,35,.025);
  --reader-scale:1;--reader-font:calc(21px * var(--reader-scale));--sidebar:232px;
}
:root[data-theme="paper"] {
  color-scheme:light;--outer:#e8e5dd;--paper:#f5f2e9;--ink:#262824;--text:#3b3a33;
  --secondary:#615f55;--muted:#7b796e;--line:#d9d4c9;--soft:#eee9df;
  --accent:#4b5347;--focus:#5c6656;--shade:rgba(41,40,33,.022);
}
:root[data-theme="dark"] {
  color-scheme:dark;--outer:#141713;--paper:#20231f;--ink:#eeeee3;--text:#dcddd0;
  --secondary:#afb3a8;--muted:#929b8e;--line:#393f39;--soft:#292e29;
  --accent:#b8cdbc;--focus:#b7cdb5;--shade:rgba(240,240,220,.035);
}
*,*::before,*::after {box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--outer);color:var(--ink);font:16px/1.68 system-ui,-apple-system,"Segoe UI",sans-serif;letter-spacing:.003em;-webkit-font-smoothing:antialiased}
button,input{font:inherit}
button{cursor:pointer}
button:focus-visible,a:focus-visible,input:focus-visible{outline:2px solid var(--focus);outline-offset:3px}
a{color:var(--accent);text-underline-offset:3px}
a:hover{text-decoration-thickness:1px}
.app{max-width:1520px;min-height:100vh;margin:0 auto;background:var(--paper)}
.progress{position:fixed;top:0;left:0;height:2px;background:var(--accent);width:0;z-index:15}
.top{height:82px;display:flex;align-items:center;justify-content:space-between;gap:16px;padding:0 clamp(22px,3.6vw,55px);border-bottom:1px solid var(--line);background:var(--paper);position:sticky;top:0;z-index:10}
.wordmark{display:flex;flex-direction:column;justify-content:center;color:var(--ink);text-decoration:none;min-width:0;gap:0}
.brand-stack{position:relative;display:block;width:211px;height:40px;flex:none}
.brand-image{display:block;width:211px;height:auto;position:absolute;top:0;left:0}
.brand-image-light{display:none}
:root[data-theme="dark"] .brand-image-ink{display:none}
:root[data-theme="dark"] .brand-image-light{display:block}
.brand-sub{font-size:8px;font-weight:550;letter-spacing:.15em;text-transform:uppercase;color:var(--secondary);white-space:nowrap;line-height:1.1;padding-left:1px}
.actions{display:flex;align-items:center;gap:8px;flex:none}
.tool{min-width:36px;min-height:36px;display:inline-flex;align-items:center;justify-content:center;padding:0 8px;border:1px solid transparent;border-radius:5px;background:transparent;color:var(--text);font-size:12px}
.tool:hover,.tool[aria-pressed="true"]{background:var(--soft);border-color:var(--line)}
.svg-icon,.svg-icon svg{display:block;height:18px;width:18px;flex:none}
.reader-setting{display:inline-flex;align-items:center;gap:2px;padding:2px 5px;border:1px solid var(--line);border-radius:6px;background:var(--shade)}
.reader-setting .tool{min-width:34px;min-height:32px;font-weight:600}
.reader-setting .tool:disabled{opacity:.3;cursor:not-allowed}
.font-level{min-width:38px;text-align:center;font-size:11px;color:var(--secondary);font-variant-numeric:tabular-nums}
.menu-toggle{display:none}
.mainlayout{display:grid;grid-template-columns:var(--sidebar) minmax(0,1fr);min-height:calc(100vh - 82px)}
.sidebar{border-right:1px solid var(--line);padding:37px 18px 28px 25px;position:sticky;top:82px;height:calc(100vh - 82px);overflow-y:auto;display:flex;flex-direction:column;gap:28px}
.sidebar-group{display:flex;flex-direction:column;gap:11px}
.kicker{font-size:11px;letter-spacing:.18em;text-transform:uppercase;color:var(--secondary);font-weight:700;padding:0 11px}
.nav{display:flex;flex-direction:column;gap:3px}
.nav a{display:block;width:100%;text-decoration:none;text-align:left;background:transparent;color:var(--secondary);padding:9px 11px;font-size:15px;border-radius:4px;line-height:1.5}
.nav a:hover{color:var(--ink);background:var(--soft)}
.nav a.active{background:var(--soft);color:var(--ink);font-weight:650}
.nav .project-link{font-family:Georgia,"Palatino Linotype",serif;font-size:17px}
.navtiny{padding:10px 11px;color:var(--muted);font-size:12px}
.sidefooter{margin-top:auto;padding:16px 10px 0;border-top:1px solid var(--line);font-size:12px;line-height:1.8;color:var(--muted)}
.sidefooter p{margin:4px 0}
.content{min-width:0}
.page{width:min(100%,980px);margin:0 auto;padding:72px clamp(25px,5.6vw,86px) 120px;min-height:75vh}
.page h1,.page h2,.page h3,.page p{margin-top:0}
.page h1,.page h2,.page h3{color:var(--ink)}
.page h1,.page h2{font-family:Georgia,"Palatino Linotype",serif;font-weight:400;letter-spacing:-.035em}
.page h1{font-size:clamp(38px,calc(64px * var(--reader-scale)),90px);line-height:1.14;margin:24px 0 26px;max-width:750px}
.page h2{font-size:clamp(25px,calc(33px * var(--reader-scale)),49px);line-height:1.25;margin-bottom:18px}
.page h3{font-size:calc(17px * var(--reader-scale));font-weight:550}
.page .lead{font-size:clamp(17px,calc(22px * var(--reader-scale)),30px);line-height:1.72;color:var(--text);max-width:665px;margin:0}
.eyebrow{font-size:12px;letter-spacing:.17em;font-weight:650;text-transform:uppercase;color:var(--secondary)}
.intro{max-width:760px}
.intro-rule{margin:65px 0 34px;border:0;border-top:1px solid var(--line)}
.section-top{display:flex;justify-content:space-between;align-items:baseline;gap:20px;margin-bottom:18px}
.section-top h2{margin:0;font-size:clamp(24px,calc(30px * var(--reader-scale)),44px)}
.textlink{text-decoration:none;font-size:13px;white-space:nowrap}
.research-list{border-top:1px solid var(--line)}
.research-entry{width:100%;border:0;border-bottom:1px solid var(--line);padding:24px 0 26px;display:flex;align-items:center;gap:20px;background:transparent;color:var(--ink);text-align:left;text-decoration:none}
.research-entry:hover .entry-name{text-decoration:underline;text-underline-offset:5px}
.entry-number{width:28px;flex:none;color:var(--muted);font-size:11px;font-variant-numeric:tabular-nums}
.entry-main{flex:1;min-width:0}
.entry-name{font-family:Georgia,"Palatino Linotype",serif;font-size:clamp(21px,calc(26px * var(--reader-scale)),39px);line-height:1.2;display:block;letter-spacing:-.025em}
.entry-desc{display:block;font-size:clamp(13px,calc(15px * var(--reader-scale)),21px);color:var(--secondary);margin-top:7px;line-height:1.5}
.entry-meta{font-size:10px;letter-spacing:.09em;text-transform:uppercase;color:var(--muted);margin-top:11px;display:block}
.note-box{border-left:2px solid var(--accent);padding:5px 0 5px 20px;margin:50px 0 0;color:var(--secondary);max-width:660px;font-size:clamp(14px,calc(16px * var(--reader-scale)),22px);line-height:1.85}
.note-box strong{color:var(--ink);font-weight:600}
.library-sub{color:var(--secondary);max-width:630px;line-height:1.75;font-size:clamp(16px,calc(19px * var(--reader-scale)),27px)}
.searchbar{display:flex;align-items:center;border:1px solid var(--line);padding:0 14px;gap:12px;margin:34px 0 25px;height:52px;background:var(--shade)}
.searchbar .svg-icon{color:var(--secondary)}
.searchbar input{width:100%;border:0;background:transparent;color:var(--ink);outline:none;font-size:15px;min-width:0}
.searchbar input::placeholder{color:var(--muted)}
.searchbar:focus-within{outline:2px solid var(--focus);outline-offset:2px}
.resultline{font-size:11px;letter-spacing:.08em;text-transform:uppercase;color:var(--muted);margin:0 0 13px}
.back{font-size:14px;text-decoration:none;display:inline-block;margin-bottom:46px}
.article{max-width:725px}
.article h1{font-size:clamp(40px,calc(70px * var(--reader-scale)),103px);margin:18px 0 20px}
.article-lead{font:calc(24px * var(--reader-scale))/1.65 Georgia,"Palatino Linotype",serif;letter-spacing:-.01em;color:var(--text);margin-bottom:32px}
.pill{display:inline-block;padding:3px 9px;border:1px solid var(--line);font-size:10px;text-transform:uppercase;letter-spacing:.10em;color:var(--secondary);border-radius:2px;vertical-align:middle}
.info-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));border-top:1px solid var(--line);border-bottom:1px solid var(--line);margin:37px 0 52px}
.info-grid>div{padding:17px 12px 17px 0;min-width:0}
.info-grid>div+div{padding-left:17px;border-left:1px solid var(--line)}
.info-grid span{display:block;color:var(--muted);font-size:11px;letter-spacing:.1em;text-transform:uppercase;margin-bottom:8px}
.info-grid strong{display:block;font-size:clamp(14px,calc(16px * var(--reader-scale)),22px);font-weight:550;overflow-wrap:anywhere;line-height:1.5}
.article section{margin:48px 0;scroll-margin-top:115px}
.article section h2{font-size:clamp(26px,calc(32px * var(--reader-scale)),46px);padding-top:6px}
.reader-text,.prose{font-family:Georgia,"Palatino Linotype",serif;font-size:var(--reader-font);line-height:1.85;color:var(--text);letter-spacing:.005em}
.reader-text p,.prose p{margin:0 0 24px}
.reader-text a,.prose a{font-size:inherit}
.chapter-no{display:block;margin-bottom:14px;font:650 10px system-ui,sans-serif;color:var(--muted);letter-spacing:.15em;text-transform:uppercase}
.toc{margin:43px 0 10px;padding:20px 0;border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.toc h2{font:650 10px system-ui,sans-serif;color:var(--secondary);letter-spacing:.17em;text-transform:uppercase;margin:0 0 10px}
.toc-items{display:flex;gap:8px 19px;flex-wrap:wrap}
.toc-items a{font-size:14px;text-decoration:none;color:var(--secondary)}
.toc-items a:hover{text-decoration:underline}
.evidence{border:1px solid var(--line);padding:22px 23px;background:var(--shade)}
.evidence h3{font-size:14px;margin-bottom:9px}
.evidence p{color:var(--secondary);font-size:clamp(13px,calc(14px * var(--reader-scale)),21px);line-height:1.8;margin-bottom:0}
.metrics-wrap{overflow-x:auto;margin:23px 0}
.metrics{border-collapse:collapse;width:100%;font:calc(15px * var(--reader-scale))/1.6 system-ui,sans-serif;min-width:390px}
.metrics td,.metrics th{padding:12px 11px;border-bottom:1px solid var(--line);text-align:left;font-weight:400}
.metrics th{color:var(--secondary);font-size:12px}
.metrics th:not(:first-child),.metrics td:not(:first-child){text-align:right;font-variant-numeric:tabular-nums}
.warning{border-left:2px solid var(--line);padding:8px 0 8px 15px;color:var(--secondary);font:14px/1.8 system-ui,sans-serif}
.empty{padding:35px 0;color:var(--secondary);border-top:1px solid var(--line);font-size:14px}
.footer{border-top:1px solid var(--line);padding:24px clamp(25px,5vw,60px);font-size:11px;color:var(--muted);display:flex;justify-content:space-between;flex-wrap:wrap;gap:10px}
.sidebar-backdrop{display:none}
.app.is-focus .mainlayout{display:block}
.app.is-focus .sidebar{display:none}
.app.is-focus .page{max-width:850px}
.app.is-focus .article{max-width:710px}
.app.is-focus .focus-tool{background:var(--soft);border-color:var(--line)}
@media (min-width:1000px){:root{--reader-font:calc(22px * var(--reader-scale))}}
@media (max-width:900px){:root{--sidebar:208px}.sidebar{padding:28px 12px}.page{padding:55px 38px 85px}.brand-stack,.brand-image{width:184px}.brand-stack{height:35px}.brand-sub{font-size:7px}}
@media (max-width:700px){
  .top{height:73px;padding:0 14px;gap:8px}
  .menu-toggle{display:inline-flex;flex:none}
  .mainlayout{display:block;min-height:calc(100vh - 73px)}
  .sidebar{display:none;position:fixed;top:73px;left:0;bottom:0;z-index:13;height:auto;width:min(83vw,310px);background:var(--paper);padding:28px 20px 38px;box-shadow:0 10px 30px rgba(0,0,0,.13)}
  .sidebar.is-open{display:flex}
  body.nav-open .sidebar-backdrop{display:block;position:fixed;z-index:12;inset:73px 0 0;border:0;background:rgba(0,0,0,.38);width:100%;height:calc(100vh - 73px)}
  .brand-stack,.brand-image{width:147px}.brand-stack{height:28px}.brand-sub{font-size:6px;letter-spacing:.09em}
  .actions{gap:0}.tool{min-width:31px;min-height:34px;padding:0 4px}.reader-setting{padding:1px 2px;gap:0}.reader-setting .tool{min-width:30px}.font-level{min-width:32px;font-size:10px}
  .search-tool{display:none}
  .page{padding:43px 24px 79px}
  .intro-rule{margin-top:44px}.section-top{flex-wrap:wrap;gap:6px 12px}
  .research-entry{gap:11px}.info-grid{grid-template-columns:1fr}
  .info-grid>div{padding:13px 0!important;border:0!important;border-bottom:1px solid var(--line)!important}
  .info-grid>div:last-child{border-bottom:0!important}
  .footer{padding:22px}

  /* Mobile reader: compact display type; article text still scales with A− / A+ */
  :root{--reader-font:calc(18px * var(--reader-scale))}
  .page h1{font-size:clamp(35px,calc(43px * var(--reader-scale)),58px);line-height:1.17;margin:18px 0 22px}
  .page h2{font-size:clamp(24px,calc(28px * var(--reader-scale)),37px)}
  .page .lead{font-size:clamp(16px,calc(18px * var(--reader-scale)),24px);line-height:1.6}
  .article h1{font-size:clamp(36px,calc(46px * var(--reader-scale)),61px);line-height:1.13;margin:16px 0 20px}
  .article-lead{font-size:clamp(17px,calc(19px * var(--reader-scale)),26px);line-height:1.56;margin-bottom:28px}
  .article section h2{font-size:clamp(23px,calc(28px * var(--reader-scale)),39px)}
  .eyebrow{font-size:10px;line-height:1.55}
  .entry-name{font-size:clamp(20px,calc(23px * var(--reader-scale)),30px)}
  .entry-desc{font-size:clamp(13px,calc(14px * var(--reader-scale)),19px)}
  .note-box{font-size:clamp(13px,calc(14px * var(--reader-scale)),19px)}
  .info-grid strong{font-size:clamp(14px,calc(15px * var(--reader-scale)),20px)}
  .metrics{font-size:calc(14px * var(--reader-scale))}
  .reader-text,.prose{line-height:1.72}
}
@media (max-width:410px){.brand-stack,.brand-image{width:130px}.brand-stack{height:25px}.brand-sub{display:none}.top{padding:0 9px}.actions .focus-tool{display:none}.top{gap:3px}}
@media print{ :root{--paper:white;--outer:white;--ink:#111;--text:#111;--secondary:#333}.top,.sidebar,.actions,.footer,.back,.toc,.progress{display:none!important}.app{border:0}.mainlayout{display:block}.page{padding:0;max-width:none}.article{max-width:none}h1{font-size:37px!important}}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}}

/* v1.4 · external links: monochrome vector arrow, no Unicode emoji rendering on iOS.
   The icon is decorative and does not alter the readable link label. */
a[target="_blank"][href^="https://"]::after,
a[target="_blank"][href^="http://"]::after {
  content:"";
  display:inline-block;
  width:.78em;
  height:.78em;
  margin-left:.22em;
  vertical-align:-.02em;
  background-color:currentColor;
  -webkit-mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3E%3Cpath d='M4 12 12 4M6.5 4H12v5.5' fill='none' stroke='black' stroke-width='1.65' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E") center / contain no-repeat;
  mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3E%3Cpath d='M4 12 12 4M6.5 4H12v5.5' fill='none' stroke='black' stroke-width='1.65' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E") center / contain no-repeat;
}