/* You Zhou — academic site stylesheet
   Tokens first (light), then dark overrides. Components only use tokens. */

:root {
  --bg: #ffffff;
  --bg-alt: #f3f4f1;
  --bg-inset: #e9ebe6;
  --ink: #15181c;
  --ink-2: #3b424a;
  --muted: #6b7480;
  --line: #dcdfe2;
  --line-strong: #b6bcc3;
  --accent: #a41e2b;        /* deep emission red (MoSe2 photoluminescence ~750 nm) */
  --accent-ink: #8a1723;
  --accent-soft: #f6e6e7;
  --lattice-dot: #2a3038;
  --lattice-faint: #c9ced4;
  --serif: 'Newsreader', 'Iowan Old Style', 'Palatino Linotype', 'Book Antiqua', Georgia, serif;
  --sans: 'IBM Plex Sans', 'Helvetica Neue', Helvetica, Arial, sans-serif;
  --mono: 'IBM Plex Mono', 'SFMono-Regular', Menlo, Consolas, monospace;
  --wrap: 1120px;
  --rail: 190px;
  --gap: 40px;
  --radius: 3px;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0f1114;
    --bg-alt: #171a1e;
    --bg-inset: #1f2329;
    --ink: #e9e7e2;
    --ink-2: #c3c0b9;
    --muted: #8f98a3;
    --line: #2a2f35;
    --line-strong: #414850;
    --accent: #e1737b;
    --accent-ink: #ee9098;
    --accent-soft: #2b1b1e;
    --lattice-dot: #d5d2cb;
    --lattice-faint: #3a4047;
  }
}
:root[data-theme="dark"] {
  --bg: #0f1114;
  --bg-alt: #171a1e;
  --bg-inset: #1f2329;
  --ink: #e9e7e2;
  --ink-2: #c3c0b9;
  --muted: #8f98a3;
  --line: #2a2f35;
  --line-strong: #414850;
  --accent: #e1737b;
  --accent-ink: #ee9098;
  --accent-soft: #2b1b1e;
  --lattice-dot: #d5d2cb;
  --lattice-faint: #3a4047;
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.6;
  font-feature-settings: "kern", "liga";
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--accent-ink); text-decoration: underline; text-underline-offset: 3px; }
a:focus-visible, button:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 2px; }
h1, h2, h3, h4 { font-family: var(--serif); font-weight: 500; line-height: 1.15; margin: 0; text-wrap: balance; color: var(--ink); }
h1 { font-size: clamp(2rem, 4.2vw, 3.1rem); letter-spacing: -0.01em; }
h2 { font-size: clamp(1.55rem, 2.6vw, 2rem); }
h3 { font-size: 1.35rem; }
h4 { font-size: 1.1rem; font-family: var(--sans); font-weight: 600; }
p { margin: 0 0 1em; }
p:last-child { margin-bottom: 0; }
sub, sup { font-size: 0.72em; line-height: 0; }
.wrap { max-width: var(--wrap); margin: 0 auto; padding: 0 24px; }
.label {
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0 0 0.6rem;
}
.lede { font-family: var(--serif); font-size: 1.32rem; line-height: 1.45; color: var(--ink); max-width: 38em; }
.prose { max-width: 66ch; }
.prose h2, .prose h3 { margin-top: 2.2rem; margin-bottom: 0.7rem; }
.prose ul { padding-left: 1.2em; }
.prose li { margin-bottom: 0.4em; }
.muted { color: var(--muted); }
.small { font-size: 0.93rem; }
.mono { font-family: var(--mono); font-variant-numeric: tabular-nums; }

/* ---------- Header ---------- */
.site-header { border-bottom: 1px solid var(--line); background: var(--bg); }
.site-header .wrap { display: flex; align-items: center; justify-content: space-between; gap: 24px; min-height: 72px; flex-wrap: wrap; }
.wordmark { display: flex; flex-direction: column; line-height: 1.15; color: var(--ink); text-decoration: none; padding: 12px 0; }
.wordmark:hover { text-decoration: none; color: var(--ink); }
.wordmark .name { font-family: var(--serif); font-size: 1.45rem; font-weight: 500; letter-spacing: 0.005em; }
.wordmark .sub { font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--muted); margin-top: 3px; }
.site-nav { display: flex; flex-wrap: wrap; gap: 4px 22px; padding: 10px 0; }
.site-nav a { color: var(--ink-2); font-size: 0.95rem; padding: 6px 0; border-bottom: 2px solid transparent; }
.site-nav a:hover { color: var(--ink); text-decoration: none; border-bottom-color: var(--line-strong); }
.site-nav a[aria-current="page"] { color: var(--ink); border-bottom-color: var(--accent); }
.site-nav a.cv { font-family: var(--mono); font-size: 0.8rem; letter-spacing: 0.08em; text-transform: uppercase; }

/* ---------- Sections with a left rail ---------- */
.sec { padding: 56px 0; border-top: 1px solid var(--line); }
.sec.alt { background: var(--bg-alt); }
.sec-grid { display: grid; grid-template-columns: var(--rail) minmax(0, 1fr); gap: 24px var(--gap); align-items: start; }
.rail { position: sticky; top: 24px; }
.rail .label { margin-bottom: 0.4rem; }
.rail p { font-size: 0.93rem; color: var(--muted); max-width: 22ch; }
@media (max-width: 820px) {
  .sec { padding: 40px 0; }
  .sec-grid { grid-template-columns: 1fr; gap: 12px; }
  .rail { position: static; }
}

/* ---------- Home: hero ---------- */
.hero { padding: 64px 0 52px; }
.hero-grid { display: grid; grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); gap: 48px; align-items: center; }
.hero h1 { margin: 0.4rem 0 1.1rem; max-width: 16em; }
.hero .who { font-family: var(--mono); font-size: 0.78rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--muted); }
.hero .who span + span::before { content: "·"; margin: 0 0.6em; color: var(--line-strong); }
.hero .vision { max-width: 40em; color: var(--ink-2); }
.hero-links { display: flex; flex-wrap: wrap; gap: 8px 22px; margin-top: 1.4rem; font-size: 0.95rem; }
.hero-links a { border-bottom: 1px solid var(--line-strong); padding-bottom: 1px; }
.hero-links a:hover { text-decoration: none; border-bottom-color: var(--accent); }
.hero-art { justify-self: center; width: 100%; max-width: 420px; }
.hero-art svg { width: 100%; height: auto; display: block; }
.hero-art figcaption { font-family: var(--mono); font-size: 0.72rem; color: var(--muted); letter-spacing: 0.04em; margin-top: 10px; text-align: center; }
@media (max-width: 820px) {
  .hero { padding: 40px 0 36px; }
  .hero-grid { grid-template-columns: 1fr; gap: 28px; }
  .hero-art { max-width: 300px; }
}

/* at-a-glance strip */
.glance { display: flex; flex-wrap: wrap; gap: 10px 36px; padding: 18px 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.glance div { display: flex; flex-direction: column; }
.glance b { font-family: var(--serif); font-weight: 500; font-size: 1.35rem; font-variant-numeric: tabular-nums; line-height: 1.1; }
.glance span { font-size: 0.8rem; color: var(--muted); letter-spacing: 0.02em; }

/* ---------- Program pillars ---------- */
.pillars { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 32px; }
.pillar h3 { font-size: 1.5rem; margin-bottom: 0.5rem; }
.pillar h3 em { font-style: italic; color: var(--accent); }
.pillar p { font-size: 0.98rem; color: var(--ink-2); }
.pillar .refs { font-family: var(--mono); font-size: 0.74rem; color: var(--muted); line-height: 1.7; margin-top: 0.6rem; }
.pillar .refs a { color: var(--muted); border-bottom: 1px dotted var(--line-strong); }
.pillar .refs a:hover { color: var(--accent); text-decoration: none; border-bottom-style: solid; }
@media (max-width: 820px) { .pillars { grid-template-columns: 1fr; gap: 26px; } }

/* ---------- Signature results ---------- */
.results { display: flex; flex-direction: column; }
.result { display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); gap: 36px; padding: 36px 0; border-top: 1px solid var(--line); align-items: start; }
.result:first-child { border-top: 0; padding-top: 0; }
.result-fig { margin: 0; }
.result-fig img, .result-fig svg { width: 100%; height: auto; border-radius: var(--radius); display: block; }
.result-fig img { border: 1px solid var(--line); }
.result-fig figcaption { font-size: 0.82rem; color: var(--muted); margin-top: 8px; line-height: 1.45; }
.result h3 { font-size: 1.6rem; margin: 0.2rem 0 0.7rem; }
.result .finding { color: var(--ink); }
.result .why { color: var(--ink-2); font-size: 0.98rem; }
.result .cite { font-size: 0.9rem; margin-top: 0.8rem; color: var(--muted); }
.result .cite a { color: var(--ink-2); border-bottom: 1px solid var(--line-strong); }
.result .cite a:hover { color: var(--accent); border-bottom-color: var(--accent); text-decoration: none; }
.result .press { font-family: var(--mono); font-size: 0.74rem; letter-spacing: 0.02em; color: var(--muted); margin-top: 0.5rem; }
.result .press a { color: var(--muted); }
.result .press a:hover { color: var(--accent); }
@media (max-width: 820px) {
  .result { grid-template-columns: 1fr; gap: 18px; padding: 28px 0; }
  .result-fig { max-width: 420px; }
}

/* ---------- Direction ---------- */
.next { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 28px; }
.next article { padding-top: 14px; border-top: 2px solid var(--ink); }
.next h3 { font-size: 1.25rem; margin-bottom: 0.5rem; }
.next p { font-size: 0.96rem; color: var(--ink-2); }
.next .support { font-family: var(--mono); font-size: 0.72rem; color: var(--muted); letter-spacing: 0.03em; margin-top: 0.5rem; }
@media (max-width: 820px) { .next { grid-template-columns: 1fr; } }

/* ---------- Recognition ---------- */
.honors { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0 40px; margin: 0; padding: 0; list-style: none; }
.honors li { display: grid; grid-template-columns: 3.2em 1fr; gap: 12px; padding: 8px 0; border-bottom: 1px solid var(--line); font-size: 0.95rem; }
.honors li span:first-child { font-family: var(--mono); font-size: 0.8rem; color: var(--muted); padding-top: 3px; font-variant-numeric: tabular-nums; }
@media (max-width: 820px) { .honors { grid-template-columns: 1fr; } }
.sponsors { margin-top: 26px; font-size: 0.93rem; color: var(--ink-2); }
.sponsors b { font-weight: 600; color: var(--ink); }

/* ---------- News list ---------- */
.news { list-style: none; margin: 0; padding: 0; }
.news li { display: grid; grid-template-columns: 7.2em 1fr; gap: 16px; padding: 12px 0; border-bottom: 1px solid var(--line); }
.news time { font-family: var(--mono); font-size: 0.8rem; color: var(--muted); padding-top: 4px; white-space: nowrap; }
.news p { margin: 0; }
.news h3 { font-family: var(--serif); font-size: 1.3rem; margin: 2.2rem 0 0.4rem; }
.more { display: inline-block; margin-top: 18px; font-size: 0.93rem; border-bottom: 1px solid var(--line-strong); }
.more:hover { text-decoration: none; border-bottom-color: var(--accent); }
@media (max-width: 600px) { .news li { grid-template-columns: 1fr; gap: 2px; } }

/* ---------- Page header (inner pages) ---------- */
.page-head { padding: 52px 0 36px; }
.page-head h1 { margin: 0.4rem 0 0.8rem; }
.page-head .lede { color: var(--ink-2); }

/* ---------- Research page ---------- */
.theme { display: grid; grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); gap: 40px; align-items: start; }
.theme figure { margin: 0; }
.theme figure img, .theme figure svg { width: 100%; height: auto; border-radius: var(--radius); }
.theme figure img { border: 1px solid var(--line); }
.theme figcaption { font-size: 0.82rem; color: var(--muted); margin-top: 8px; }
.theme h2 { margin-bottom: 0.6rem; }
.theme .q { font-family: var(--serif); font-style: italic; font-size: 1.15rem; color: var(--ink-2); margin-bottom: 1rem; }
.theme ul.papers { list-style: none; padding: 0; margin: 1rem 0 0; }
.theme ul.papers li { font-size: 0.92rem; color: var(--ink-2); padding: 6px 0; border-top: 1px solid var(--line); }
.theme ul.papers li a { color: var(--ink); }
.theme ul.papers li .j { font-family: var(--mono); font-size: 0.74rem; color: var(--muted); margin-left: 0.4em; }
@media (max-width: 820px) { .theme { grid-template-columns: 1fr; } }
.methods { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 24px 32px; }
.methods h4 { margin-bottom: 0.3rem; }
.methods p { font-size: 0.93rem; color: var(--ink-2); }
@media (max-width: 820px) { .methods { grid-template-columns: 1fr; } }
.funding { list-style: none; margin: 0; padding: 0; }
.funding li { display: grid; grid-template-columns: 6.2em 1fr; gap: 14px; padding: 9px 0; border-bottom: 1px solid var(--line); font-size: 0.94rem; }
.funding li span:first-child { font-family: var(--mono); font-size: 0.78rem; color: var(--muted); padding-top: 3px; white-space: nowrap; }
.funding .agency { color: var(--muted); }

/* ---------- Publications ---------- */
.pub-tools { display: flex; flex-wrap: wrap; gap: 10px 26px; align-items: baseline; margin-bottom: 8px; font-size: 0.93rem; }
.pubs { list-style: none; margin: 0; padding: 0; counter-reset: pub; }
.pubs li { padding: 12px 0; border-bottom: 1px solid var(--line); font-size: 0.95rem; line-height: 1.5; }
.pubs li .t { display: block; font-family: var(--serif); font-size: 1.12rem; line-height: 1.3; color: var(--ink); margin-bottom: 3px; }
.pubs li .t a { color: var(--ink); }
.pubs li .t a:hover { color: var(--accent); text-decoration: none; }
.pubs li .a { color: var(--ink-2); }
.pubs li .a b { font-weight: 600; color: var(--ink); }
.pubs li .j { color: var(--ink-2); }
.pubs li .j i { color: var(--ink); }
.pubs li .tag { font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--accent); margin-left: 0.5em; }
.pubs li .note { display: block; font-size: 0.84rem; color: var(--muted); margin-top: 3px; }
.pubs li .note a { color: var(--muted); border-bottom: 1px dotted var(--line-strong); }
.pubs li .note a:hover { color: var(--accent); text-decoration: none; }
.year-head { font-family: var(--mono); font-size: 0.78rem; letter-spacing: 0.12em; color: var(--muted); margin: 2.2rem 0 0.2rem; padding-bottom: 6px; border-bottom: 2px solid var(--ink); }
.year-head:first-of-type { margin-top: 0.4rem; }
.pub-stats { display: flex; flex-wrap: wrap; gap: 8px 28px; font-size: 0.9rem; color: var(--ink-2); }
.pub-stats b { font-family: var(--serif); font-weight: 500; font-size: 1.2rem; color: var(--ink); margin-right: 0.3em; }

/* ---------- People ---------- */
.pi { display: grid; grid-template-columns: 220px minmax(0, 1fr); gap: 36px; align-items: start; }
.pi img { border-radius: var(--radius); aspect-ratio: 4 / 5; object-fit: cover; width: 100%; }
.pi .bio { max-width: 60ch; }
.pi dl { display: grid; grid-template-columns: 6.5em 1fr; gap: 6px 14px; margin: 1rem 0 0; font-size: 0.93rem; }
.pi dt { font-family: var(--mono); font-size: 0.76rem; color: var(--muted); padding-top: 3px; }
.pi dd { margin: 0; color: var(--ink-2); }
@media (max-width: 700px) { .pi { grid-template-columns: 1fr; } .pi img { max-width: 220px; } }
.roster { display: grid; grid-template-columns: repeat(auto-fill, minmax(190px, 1fr)); gap: 28px 24px; }
.person { display: flex; flex-direction: column; gap: 8px; }
.avatar { position: relative; aspect-ratio: 4 / 5; background: var(--bg-inset); border-radius: var(--radius); overflow: hidden; display: grid; place-items: center; }
.avatar img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; }
.avatar .initials { font-family: var(--serif); font-size: 2rem; color: var(--muted); letter-spacing: 0.04em; }
.person b { font-weight: 600; font-size: 1rem; }
.person p { font-size: 0.88rem; color: var(--ink-2); margin: 0; line-height: 1.45; }
.person .now { color: var(--muted); }
.group-title { font-family: var(--serif); font-size: 1.35rem; margin: 2.4rem 0 1rem; padding-bottom: 6px; border-bottom: 1px solid var(--line-strong); }
.group-title:first-of-type { margin-top: 0; }
.namelist { columns: 2; column-gap: 40px; padding: 0; margin: 0; list-style: none; font-size: 0.94rem; }
.namelist li { break-inside: avoid; padding: 4px 0; border-bottom: 1px solid var(--line); color: var(--ink-2); }
.namelist li b { color: var(--ink); font-weight: 500; }
@media (max-width: 600px) { .namelist { columns: 1; } }
.join { background: var(--bg-alt); border-left: 3px solid var(--accent); padding: 20px 24px; max-width: 66ch; }
.join h3 { margin-bottom: 0.5rem; }
.join p { font-size: 0.96rem; }

/* ---------- Highlights (No Jargon) ---------- */
.post { display: grid; grid-template-columns: minmax(0, 4fr) minmax(0, 8fr); gap: 36px; padding: 40px 0; border-top: 1px solid var(--line); align-items: start; }
.post:first-of-type { border-top: 0; padding-top: 0; }
.post figure { margin: 0; }
.post figure img { border: 1px solid var(--line); border-radius: var(--radius); width: 100%; }
.post figcaption { font-size: 0.82rem; color: var(--muted); margin-top: 8px; line-height: 1.45; }
.post .label { margin-bottom: 0.3rem; }
.post h2 { font-size: 1.55rem; margin-bottom: 0.8rem; }
.post .body { max-width: 66ch; }
.post .body p { color: var(--ink-2); }
.post .body p.src { font-size: 0.9rem; color: var(--muted); }
.post.nofig { grid-template-columns: 1fr; }
.post.nofig .body { grid-column: 1 / -1; }
@media (max-width: 820px) { .post { grid-template-columns: 1fr; gap: 16px; } .post figure { max-width: 420px; } }
.toc { display: flex; flex-wrap: wrap; gap: 6px 18px; font-size: 0.88rem; margin-top: 12px; }
.toc a { color: var(--ink-2); border-bottom: 1px solid var(--line); }
.toc a:hover { text-decoration: none; color: var(--accent); border-bottom-color: var(--accent); }

/* ---------- Gallery ---------- */
.gallery { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 28px 24px; }
.gallery figure { margin: 0; }
.gallery img { width: 100%; aspect-ratio: 3 / 2; object-fit: cover; border-radius: var(--radius); border: 1px solid var(--line); }
.gallery figcaption { font-size: 0.88rem; color: var(--ink-2); margin-top: 8px; }

/* ---------- Footer ---------- */
.site-footer { border-top: 1px solid var(--line); background: var(--bg-alt); padding: 40px 0 48px; margin-top: 24px; font-size: 0.9rem; color: var(--ink-2); }
.site-footer .wrap { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 24px 40px; }
.site-footer .label { margin-bottom: 0.4rem; }
.site-footer p { margin: 0 0 0.3em; }
.site-footer a { color: var(--ink-2); }
.site-footer a:hover { color: var(--accent); }
.site-footer .fine { grid-column: 1 / -1; font-size: 0.78rem; color: var(--muted); margin-top: 8px; font-family: var(--mono); }
@media (max-width: 700px) { .site-footer .wrap { grid-template-columns: 1fr; } }

@media (prefers-reduced-motion: no-preference) {
  a, .site-nav a { transition: color .15s ease, border-color .15s ease; }
}
@media print {
  .site-nav, .site-footer .fine { display: none; }
  body { font-size: 11pt; }
  a { color: inherit; }
}