:root{
  --ink:#22303e;
  --ink-soft:#54626f;
  --porcelain:#f4f5f1;
  --bronze:#8a6f42;
  --bronze-line:#a08653;
  --cinnabar:#a83c2b;
  --rule:#d9dbd3;
}
@media (prefers-color-scheme: dark){
  :root:not([data-theme="light"]){
    --ink:#e8e6df;
    --ink-soft:#a9adb3;
    --porcelain:#171e26;
    --bronze:#b39a67;
    --bronze-line:#93794a;
    --cinnabar:#c05540;
    --rule:#333d47;
  }
}
:root[data-theme="dark"]{
  --ink:#e8e6df;
  --ink-soft:#a9adb3;
  --porcelain:#171e26;
  --bronze:#b39a67;
  --bronze-line:#93794a;
  --cinnabar:#c05540;
  --rule:#333d47;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  background:var(--porcelain);
  color:var(--ink);
  font-family:'Spectral', Georgia, serif;
  font-weight:400;
  line-height:1.75;
  -webkit-font-smoothing:antialiased;
}
body[data-lang="zh-Hans"]{font-family:'Spectral','Noto Serif SC', serif; line-height:2.05}
body[data-lang="zh-Hant"]{font-family:'Spectral','Noto Serif TC', serif; line-height:2.05}

/* language visibility */
.l{display:none}
body[data-lang="en"] .l.en{display:inline}
body[data-lang="zh-Hans"] .l.hans{display:inline}
body[data-lang="zh-Hant"] .l.hant{display:inline}
body[data-lang="en"] p.l.en, body[data-lang="en"] div.l.en{display:block}
body[data-lang="zh-Hans"] p.l.hans, body[data-lang="zh-Hans"] div.l.hans{display:block}
body[data-lang="zh-Hant"] p.l.hant, body[data-lang="zh-Hant"] div.l.hant{display:block}

header{
  max-width:860px;margin:0 auto;padding:1.4rem 1.4rem 0;
  display:flex;justify-content:space-between;align-items:center;
  gap:.8rem 1.4rem;flex-wrap:wrap;
}
.seal{
  width:44px;height:44px;background:var(--cinnabar);color:#f6f1e8;
  display:grid;place-items:center;
  font-family:'Noto Serif TC', serif;font-weight:600;font-size:.95rem;
  line-height:1.15;text-align:center;letter-spacing:.05em;
  border-radius:3px;
  box-shadow:0 1px 0 rgba(0,0,0,.15);
  user-select:none;text-decoration:none;flex:0 0 auto;
}
.menu{
  display:flex;gap:.1rem .35rem;flex-wrap:wrap;align-items:center;
  margin-right:auto;
}
.menu a{
  text-decoration:none;color:var(--ink-soft);
  font-size:.95rem;padding:.25rem .55rem;border-radius:2px;
  border-bottom:2px solid transparent;
}
.menu a:hover{color:var(--ink)}
.menu a.active{color:var(--ink);border-bottom-color:var(--bronze)}
.langs{display:flex;gap:.25rem}
.langs button{
  appearance:none;background:none;border:1px solid transparent;
  font-family:inherit;font-size:.85rem;color:var(--ink-soft);
  padding:.3rem .6rem;cursor:pointer;border-radius:2px;
}
.langs button:hover{color:var(--ink)}
.langs button[aria-pressed="true"]{color:var(--ink);border-color:var(--rule)}
.langs button:focus-visible{outline:2px solid var(--bronze);outline-offset:2px}

.hero{
  max-width:720px;margin:0 auto;text-align:center;
  padding:3.2rem 1.4rem 2.4rem;
}
.compass{width:min(216px,58vw);height:auto;display:block;margin:0 auto 2.2rem}
#needle{transform-origin:110px 110px}
@media (prefers-reduced-motion: no-preference){
  #needle{animation:settle 1.8s cubic-bezier(.23,1,.32,1) both}
  @keyframes settle{from{transform:rotate(-40deg)}to{transform:rotate(0deg)}}
}
.wordmark{
  font-weight:600;
  font-size:clamp(2rem,6vw,2.9rem);
  letter-spacing:.02em;
  line-height:1.25;
}
body[data-lang="zh-Hans"] .wordmark,body[data-lang="zh-Hant"] .wordmark{letter-spacing:.16em}
.tagline{
  margin-top:.9rem;color:var(--ink-soft);
  font-size:clamp(1rem,2.6vw,1.15rem);
  font-style:italic;
}
body[data-lang="zh-Hans"] .tagline,body[data-lang="zh-Hant"] .tagline{font-style:normal}

.divider{max-width:720px;margin:0 auto;padding:0 1.4rem}
.divider hr{border:none;border-top:1px solid var(--rule)}

/* inner page header */
.page-head{
  max-width:720px;margin:0 auto;text-align:center;
  padding:3rem 1.4rem 1.2rem;
}
.page-head h1{
  font-weight:600;font-size:clamp(1.7rem,5vw,2.3rem);letter-spacing:.03em;
}
body[data-lang="zh-Hans"] .page-head h1,body[data-lang="zh-Hant"] .page-head h1{letter-spacing:.14em}
.page-head .sub{
  margin-top:.7rem;color:var(--ink-soft);
  font-size:clamp(.98rem,2.4vw,1.08rem);
}
.page-head::after{
  content:"";display:block;width:2.4rem;height:1px;
  background:var(--bronze-line);margin:1.6rem auto 0;
}

main{
  max-width:640px;margin:0 auto;
  padding:2.6rem 1.4rem 1rem;
  font-size:1.06rem;
}
main p{margin-bottom:1.6em;color:var(--ink)}
main p:first-of-type .lead-mark{color:var(--bronze);font-weight:500}
.credo{
  text-align:center;
  font-size:clamp(1.25rem,3.4vw,1.55rem);
  font-weight:500;
  margin:2.6rem 0;
  color:var(--ink);
}
.credo::before,.credo::after{
  content:"";display:block;width:2.4rem;height:1px;
  background:var(--bronze-line);margin:1.2rem auto;
}

/* research areas */
.area{margin:0 0 2.6rem}
.area h2{
  font-weight:600;font-size:1.22rem;letter-spacing:.02em;
  margin-bottom:.5rem;color:var(--ink);
}
body[data-lang="zh-Hans"] .area h2,body[data-lang="zh-Hant"] .area h2{letter-spacing:.1em}
.area h2::before{
  content:"";display:inline-block;width:.55em;height:.55em;
  border:1.5px solid var(--bronze);transform:rotate(45deg);
  margin-right:.6em;vertical-align:baseline;
}
.area p{margin-bottom:0;color:var(--ink)}
.area + .area{border-top:1px solid var(--rule);padding-top:2.4rem}

/* empty state */
.empty{
  text-align:center;
  border:1px dashed var(--bronze-line);
  border-radius:4px;
  padding:2.6rem 1.6rem;
  margin:1rem 0 2rem;
  color:var(--ink-soft);
}
.empty .mark{
  font-size:1.6rem;color:var(--bronze);display:block;margin-bottom:.8rem;
}
.empty p{margin-bottom:0;color:var(--ink-soft)}

/* contact */
.contact-block{text-align:center;margin:1.4rem 0 2.4rem}
.contact-block .email{
  display:inline-block;
  font-size:clamp(1.15rem,3.4vw,1.5rem);
  font-weight:500;letter-spacing:.02em;
  color:var(--ink);text-decoration:none;
  border-bottom:2px solid var(--bronze);
  padding-bottom:.15rem;
}
.contact-block .email:hover{color:var(--bronze)}
.contact-note{color:var(--ink-soft);font-size:.98rem;text-align:center}

a.plain{color:var(--bronze);text-decoration:none}
a.plain:hover{text-decoration:underline}

footer{
  max-width:860px;margin:2.5rem auto 0;padding:1.6rem 1.4rem 2.6rem;
  border-top:1px solid var(--rule);
  display:flex;justify-content:space-between;gap:.4rem 1rem;flex-wrap:wrap;
  color:var(--ink-soft);font-size:.88rem;
}
footer a{color:var(--ink-soft);text-decoration:none}
footer a:hover{color:var(--ink)}