/* Dongho Yee — personal site. Plain CSS, no build step. */
:root {
  --bg: #ffffff;
  --bg-soft: #f3f6f8;
  --ink: #1c2733;
  --navy: #1f3b57;
  --teal: #1f6f8b;
  --slate: #5b6670;
  --rule: #d5dce2;
  --card: #ffffff;
  --shadow: 0 1px 2px rgba(16, 24, 40, 0.06), 0 8px 24px rgba(16, 24, 40, 0.06);
  --serif: Charter, "Bitstream Charter", "Source Serif 4", Georgia, "Times New Roman", serif;
  --sans: "Avenir Next", Avenir, Inter, "Helvetica Neue", "Segoe UI", Roboto, Arial, sans-serif;
  --maxw: 1000px;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0f1620;
    --bg-soft: #151e2a;
    --ink: #e6ebf0;
    --navy: #a9cbe6;
    --teal: #7cc0d8;
    --slate: #9aa5b1;
    --rule: #2a3642;
    --card: #141d28;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.4), 0 8px 24px rgba(0, 0, 0, 0.35);
  }
}
:root[data-theme="dark"] {
  --bg: #0f1620; --bg-soft: #151e2a; --ink: #e6ebf0; --navy: #a9cbe6; --teal: #7cc0d8;
  --slate: #9aa5b1; --rule: #2a3642; --card: #141d28;
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.4), 0 8px 24px rgba(0, 0, 0, 0.35);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--serif);
  font-size: 17px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--teal); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 2px; }
img, video { max-width: 100%; height: auto; display: block; }
h1, h2, h3, h4 { font-family: var(--sans); color: var(--navy); margin: 0; line-height: 1.2; }
h2 { font-size: 13px; letter-spacing: 0.14em; text-transform: uppercase; font-weight: 600;
     padding-bottom: 8px; border-bottom: 1px solid var(--rule); margin-bottom: 22px; }
h3 { font-size: 21px; font-weight: 600; margin-bottom: 8px; }
h4 { font-size: 16px; font-weight: 600; margin-bottom: 4px; }
p { margin: 0 0 12px; }
.muted { color: var(--slate); }
.small { font-size: 14.5px; }
.sans { font-family: var(--sans); }

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }
section { padding: 46px 0 12px; }

/* nav */
.nav { position: sticky; top: 0; z-index: 10; background: color-mix(in srgb, var(--bg) 88%, transparent);
       backdrop-filter: saturate(1.4) blur(10px); border-bottom: 1px solid var(--rule); }
.nav .wrap { display: flex; align-items: center; justify-content: space-between; height: 54px; gap: 16px; }
.brand { font-family: var(--sans); font-weight: 700; color: var(--navy); font-size: 17px; }
.nav ul { list-style: none; display: flex; gap: 18px; margin: 0; padding: 0; font-family: var(--sans); font-size: 14px; }
.nav ul a { color: var(--ink); }
.nav .cta { font-family: var(--sans); font-size: 13.5px; font-weight: 600; color: var(--navy);
            border: 1px solid var(--rule); padding: 6px 11px; border-radius: 8px; white-space: nowrap; }
.nav .cta:hover { background: var(--bg-soft); text-decoration: none; }
@media (max-width: 720px) { .nav ul { display: none; } }

/* hero */
.hero { padding: 56px 0 26px; }
.hero .grid { display: grid; grid-template-columns: 1fr 190px; gap: 36px; align-items: start; }
@media (max-width: 720px) { .hero .grid { grid-template-columns: 1fr; } .hero img { width: 150px; } }
.hero img { width: 190px; border-radius: 14px; box-shadow: var(--shadow); }
.hero h1 { font-size: 46px; font-weight: 700; letter-spacing: -0.01em; }
.hero .role { font-family: var(--sans); font-size: 17px; margin: 8px 0 18px; }
.hero .lead { font-size: 18.5px; }
.facts { display: flex; flex-wrap: wrap; gap: 8px 10px; margin: 16px 0 6px; padding: 0; list-style: none;
         font-family: var(--sans); font-size: 13.5px; }
.facts li { border: 1px solid var(--rule); border-radius: 999px; padding: 4px 11px; color: var(--ink); background: var(--bg-soft); }
.facts li.strong { border-color: var(--navy); color: var(--navy); font-weight: 600; background: transparent; }
.links { display: flex; flex-wrap: wrap; gap: 6px 18px; margin-top: 14px; font-family: var(--sans); font-size: 14.5px; }
.links a { display: inline-flex; align-items: center; gap: 6px; }
.orcid { width: 15px; height: 15px; border-radius: 50%; background: #a6ce39; color: #fff; font: 700 8px/15px var(--sans);
         text-align: center; display: inline-block; }

/* now */
.now { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; margin: 4px 0 30px; }
@media (max-width: 720px) { .now { grid-template-columns: 1fr; } }
.now > div { border-left: 3px solid var(--navy); padding: 2px 0 2px 14px; }
.now .k { display: block; font-family: var(--sans); font-size: 12.5px; letter-spacing: 0.08em; text-transform: uppercase; color: var(--slate); border: 0; padding: 0; margin-bottom: 4px; }
.now .v { display: block; font-size: 16px; border: 0; padding: 0; }

/* research */
.work { display: grid; grid-template-columns: 1.15fr 1fr; gap: 28px; align-items: start; padding: 26px 0; border-top: 1px solid var(--rule); }
.work:first-of-type { border-top: 0; padding-top: 6px; }
.work.flip { grid-template-columns: 1fr 1.15fr; }
.work.flip .media { order: 2; }
@media (max-width: 820px) { .work, .work.flip { grid-template-columns: 1fr; } .work.flip .media { order: 0; } }
.media img, .media video { border-radius: 10px; box-shadow: var(--shadow); width: 100%; }
.media .pair { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
.media figcaption, .cap { font-family: var(--sans); font-size: 13px; color: var(--slate); margin-top: 8px; line-height: 1.4; }
.media figure { margin: 0; }
.media figure + figure { margin-top: 12px; }
.kicker { font-family: var(--sans); font-size: 12.5px; letter-spacing: 0.1em; text-transform: uppercase; color: var(--teal); margin-bottom: 6px; }
.work ul { padding-left: 18px; margin: 6px 0 10px; }
.work li { margin-bottom: 5px; }
.refs { font-family: var(--sans); font-size: 14px; display: flex; flex-wrap: wrap; gap: 6px 16px; }

/* publications */
.pubs { list-style: none; padding: 0; margin: 0; counter-reset: pub; }
.pubs li { position: relative; padding-left: 38px; margin-bottom: 14px; }
.pubs li::before { counter-increment: pub; content: "[" counter(pub) "]"; position: absolute; left: 0; top: 0;
                   font-family: var(--sans); font-size: 14px; color: var(--slate); }
.pubs .t { font-style: italic; }
.pubs .v { color: var(--slate); }
.pubs .me { font-weight: 700; }
.pubs .l { font-family: var(--sans); font-size: 14px; }

/* cards */
.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(168px, 1fr)); gap: 14px; }
.card { background: var(--card); border: 1px solid var(--rule); border-radius: 12px; padding: 14px; }
.card img { width: 44px; height: 44px; border-radius: 10px; margin-bottom: 10px; object-fit: contain; }
.card h4 { font-size: 15.5px; }
.card p { font-size: 14px; color: var(--slate); margin: 0; line-height: 1.45; }
.card .y { font-family: var(--sans); font-size: 12px; color: var(--slate); }

dl.plain { display: grid; grid-template-columns: 150px 1fr; gap: 8px 18px; margin: 0 0 12px; }
dl.plain dt { font-family: var(--sans); font-size: 14px; color: var(--slate); }
dl.plain dd { margin: 0; }
@media (max-width: 600px) { dl.plain { grid-template-columns: 1fr; gap: 2px 0; } dl.plain dd { margin-bottom: 10px; } }

footer { border-top: 1px solid var(--rule); margin-top: 50px; padding: 24px 0 40px; font-family: var(--sans); font-size: 13.5px; color: var(--slate); }
footer .wrap { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px; }

/* videos & gallery */
.videos { display: grid; grid-template-columns: 1fr 1fr; gap: 22px; }
@media (max-width: 720px) { .videos { grid-template-columns: 1fr; } }
.videos figure { margin: 0; }
.videos video { width: 100%; border-radius: 10px; box-shadow: var(--shadow); background: #000; aspect-ratio: 16 / 9; }
.videos figcaption { font-family: var(--sans); font-size: 13.5px; color: var(--slate); margin-top: 8px; line-height: 1.45; }
.videos figcaption strong { color: var(--ink); font-weight: 600; }
.gallery { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px 16px; }
@media (max-width: 900px) { .gallery { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 520px) { .gallery { grid-template-columns: 1fr; } }
.gallery figure { margin: 0; }
.gallery img { width: 100%; aspect-ratio: 3 / 2; object-fit: cover; border-radius: 8px; box-shadow: var(--shadow); transition: transform .15s ease; }
.gallery a:hover img { transform: translateY(-2px); }
.gallery figcaption { font-family: var(--sans); font-size: 12.5px; color: var(--slate); margin-top: 7px; line-height: 1.4; }

.card .clinks { display: flex; flex-wrap: wrap; gap: 4px 12px; margin-top: 10px; font-family: var(--sans); font-size: 13px; }
.card .clinks a.play { font-weight: 600; }