@import url('https://fonts.googleapis.com/css2?family=Fraunces:opsz,wght@9..144,340..600&family=Libre+Franklin:wght@400;500;600;700&family=IBM+Plex+Mono:wght@400;500&display=swap');

  :root {
    color-scheme: light;
    --paper: #f5f3ee;
    --ink: #1c2431;
    --ink-soft: #454b57;
    --muted: #78766b;
    --rule: #dcd8cc;
    --accent: #a8540f;
    --accent-ink: #fffaf4;
    --accent-bg: rgba(168, 84, 15, 0.09);
    --accent-soft: #3f6e6a;
    --accent-soft-bg: rgba(63, 110, 106, 0.1);
    --focus: #3f6e6a;
  }

  @media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) {
      color-scheme: dark;
      --paper: #171b24;
      --ink: #ece8df;
      --ink-soft: #c7c3b8;
      --muted: #928d7d;
      --rule: #333a48;
      --accent: #e08a4f;
      --accent-ink: #211404;
      --accent-bg: rgba(224, 138, 79, 0.13);
      --accent-soft: #7bbab3;
      --accent-soft-bg: rgba(123, 186, 179, 0.12);
      --focus: #7bbab3;
    }
  }

  :root[data-theme="dark"] {
    color-scheme: dark;
    --paper: #171b24;
    --ink: #ece8df;
    --ink-soft: #c7c3b8;
    --muted: #928d7d;
    --rule: #333a48;
    --accent: #e08a4f;
    --accent-ink: #211404;
    --accent-bg: rgba(224, 138, 79, 0.13);
    --accent-soft: #7bbab3;
    --accent-soft-bg: rgba(123, 186, 179, 0.12);
    --focus: #7bbab3;
  }

  * { box-sizing: border-box; }

  html, body { margin: 0; padding: 0; }

  body {
    background: var(--paper);
    color: var(--ink);
    font-family: 'Libre Franklin', system-ui, -apple-system, 'Segoe UI', sans-serif;
    font-size: 16.5px;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
  }

  ::selection { background: var(--accent-soft-bg); color: var(--ink); }

  a { color: var(--ink); text-decoration-color: var(--rule); text-underline-offset: 3px; }
  a:hover { text-decoration-color: var(--accent); color: var(--accent); }
  a:focus-visible, button:focus-visible { outline: 2px solid var(--focus); outline-offset: 3px; border-radius: 2px; }

  .page { max-width: 720px; margin: 0 auto; padding: 0 1.75rem 5rem; }

  h1, h2, h3 { font-family: 'Fraunces', Georgia, serif; font-weight: 560; text-wrap: balance; color: var(--ink); }

  .eyebrow {
    font-family: 'IBM Plex Mono', ui-monospace, monospace;
    font-size: 0.72rem;
    letter-spacing: 0.11em;
    text-transform: uppercase;
    color: var(--muted);
  }

  /* ---------- Site header (persistent across pages) ---------- */

  .site-header {
    max-width: 720px;
    margin: 0 auto;
    padding: 1.9rem 1.75rem 2.6rem;
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    gap: 1rem;
  }
  .site-header .brand {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 0.78rem;
    letter-spacing: 0.03em;
    color: var(--ink);
    text-decoration: none;
    border-bottom: none;
  }
  .site-header .brand:hover { color: var(--accent); }

  nav.site-nav { display: flex; gap: 1.4rem; flex-wrap: wrap; }
  nav.site-nav a {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 0.78rem;
    letter-spacing: 0.02em;
    color: var(--ink-soft);
    text-decoration: none;
    border-bottom: 1px solid transparent;
    padding-bottom: 2px;
  }
  nav.site-nav a:hover { border-bottom-color: var(--accent); color: var(--accent); }
  nav.site-nav a.active { color: var(--accent); border-bottom-color: var(--accent); }

  /* ---------- Hero (home only) ---------- */

  .hero { position: relative; padding-bottom: 2.4rem; }

  h1.name {
    font-size: clamp(2.5rem, 6vw, 3.4rem);
    line-height: 1.05;
    margin: 0 0 0.55rem;
    letter-spacing: -0.01em;
  }

  p.tagline { font-size: 1.14rem; color: var(--ink-soft); max-width: 34rem; margin: 0; }
  p.tagline strong { color: var(--ink); font-weight: 600; }

  /* ---------- Cover panel: a shared frame for the generative covers ---------- */

  .cover-panel {
    position: relative;
    overflow: hidden;
    border-radius: 6px;
    border: 1px solid var(--rule);
    background: color-mix(in srgb, var(--ink) 3%, var(--paper));
    padding: 2.8rem 1.7rem 2.5rem;
    margin: 0.4rem 0 2rem;
  }
  .cover-panel canvas {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    display: block;
    pointer-events: none;
  }
  .lattice-canvas { opacity: 0.62; }
  .cover-panel-content { position: relative; z-index: 1; }

  /* Biography cover: a 3D crystal lattice with an electron cloud */
  .bio-cover { min-height: 18rem; display: flex; align-items: flex-end; }
  .crystal-canvas { opacity: 0.9; }

  /* Teaching cover: a contour-integration diagram that draws itself */
  .teaching-cover { min-height: 16rem; display: flex; align-items: flex-end; }
  .contour-canvas { opacity: 0.9; }

  .tags { display: flex; flex-wrap: wrap; gap: 0.55rem; margin-bottom: 1.9rem; }
  .tag {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 0.74rem;
    letter-spacing: 0.02em;
    color: var(--accent-soft);
    background: var(--accent-soft-bg);
    border: 1px solid color-mix(in srgb, var(--accent-soft) 35%, transparent);
    border-radius: 3px;
    padding: 0.3rem 0.6rem;
  }

  .contact-row { display: flex; flex-wrap: wrap; gap: 1.3rem 1.6rem; align-items: baseline; }
  .contact-row a { font-size: 0.92rem; text-decoration: none; border-bottom: 1px solid var(--rule); padding-bottom: 1px; }
  .contact-row a:hover { border-bottom-color: var(--accent); }
  .contact-row .arrow { font-family: 'IBM Plex Mono', monospace; font-size: 0.86rem; }
  .placeholder { color: var(--muted); font-style: italic; }

  /* ---------- Callout ---------- */

  .callout {
    border: 1px solid color-mix(in srgb, var(--accent) 40%, var(--rule));
    background: var(--accent-bg);
    border-radius: 4px;
    padding: 1.1rem 1.3rem;
    margin: 0.5rem 0 3.2rem;
    display: flex;
    gap: 0.9rem;
    align-items: baseline;
  }
  .callout .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--accent); flex: none; transform: translateY(-1px); }
  .callout p { margin: 0; font-size: 0.96rem; color: var(--ink-soft); }
  .callout strong { color: var(--ink); }

  /* ---------- Sections ---------- */

  section { margin-bottom: 3.2rem; }

  h2.section-title {
    font-size: 1.5rem;
    display: flex;
    align-items: baseline;
    gap: 0.7rem;
    margin: 0 0 1.3rem;
    padding-bottom: 0.6rem;
    border-bottom: 1px solid var(--rule);
  }
  h2.section-title .eyebrow { font-size: 0.68rem; }

  p.lede { color: var(--ink-soft); max-width: 62ch; }

  .interest-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); gap: 1.4rem; margin-top: 1.4rem; }
  .interest-card h3 { font-size: 1.03rem; font-weight: 560; margin: 0 0 0.35rem; }
  .interest-card p { margin: 0; font-size: 0.91rem; color: var(--muted); line-height: 1.55; }

  .edu-row { display: flex; justify-content: space-between; gap: 1.5rem; align-items: baseline; padding: 0.9rem 0; border-bottom: 1px solid var(--rule); }
  .edu-row:last-child { border-bottom: none; }
  .edu-main strong { display: block; font-size: 1.02rem; }
  .edu-main span { color: var(--muted); font-size: 0.9rem; }
  .edu-year { font-family: 'IBM Plex Mono', monospace; font-size: 0.82rem; color: var(--muted); white-space: nowrap; }

  .skill-groups { display: grid; gap: 2.2rem; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); align-items: start; }
  .skill-category h3 { font-size: 1.02rem; font-weight: 560; margin: 0 0 1rem; color: var(--ink); }
  .skill-row { margin-bottom: 1.1rem; }
  .skill-row:last-child { margin-bottom: 0; }
  .skill-label {
    display: block;
    font-family: 'IBM Plex Mono', monospace;
    font-size: 0.76rem;
    font-weight: 500;
    letter-spacing: 0.03em;
    text-transform: uppercase;
    color: var(--muted);
    margin-bottom: 0.35rem;
  }
  .skill-desc { margin: 0; color: var(--ink-soft); font-size: 0.91rem; line-height: 1.55; }

  /* ---------- Publications ---------- */

  .pub-list { list-style: none; margin: 0; padding: 0; }
  .pub { display: grid; grid-template-columns: 3.6rem 1fr; gap: 1.1rem; padding: 1.15rem 0; border-bottom: 1px solid var(--rule); }
  .pub:last-child { border-bottom: none; }
  .pub-year { font-family: 'IBM Plex Mono', monospace; font-size: 0.88rem; color: var(--accent-soft); padding-top: 0.15rem; }
  .pub-title { font-size: 1rem; font-weight: 600; margin: 0 0 0.3rem; line-height: 1.4; }
  .pub-title a { text-decoration: none; border-bottom: 1px solid var(--rule); }
  .pub-title a:hover { border-bottom-color: var(--accent); }
  .pub-authors { font-size: 0.89rem; color: var(--ink-soft); margin: 0 0 0.3rem; }
  .pub-authors .me { color: var(--ink); font-weight: 600; }
  .pub-venue { font-size: 0.86rem; color: var(--muted); font-style: italic; }
  .pub-meta { display: inline-flex; align-items: center; gap: 0.4rem; margin-left: 0.6rem; font-family: 'IBM Plex Mono', monospace; font-style: normal; font-size: 0.76rem; color: var(--muted); }
  .pub-meta::before { content: '·'; }
  .pub-empty { color: var(--muted); font-style: italic; font-size: 0.92rem; }

  /* ---------- Sub-page header (Teaching / Biography / Contact) ---------- */

  .page-hero { padding: 0.5rem 0 2.6rem; border-bottom: 1px solid var(--rule); margin-bottom: 2.8rem; }
  .page-hero h1 { font-size: clamp(2.1rem, 5vw, 2.7rem); margin: 0.4rem 0 0; }

  /* ---------- Biography ---------- */

  .bio-copy { max-width: 62ch; }
  .bio-copy p { margin: 0 0 1.25rem; color: var(--ink); }
  .bio-copy p:first-of-type { font-size: 1.08rem; }

  .bio-quote {
    margin: 2.2rem 0;
    padding: 1rem 0 1rem 1.2rem;
    border-left: 2px solid var(--accent-soft);
    font-family: 'Fraunces', Georgia, serif;
    font-size: 1.15rem;
    font-style: italic;
    color: var(--muted);
  }

  /* ---------- Contact / Teaching rows ---------- */

  .contact-list { list-style: none; margin: 0; padding: 0; }
  .contact-item {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    gap: 1.5rem;
    padding: 1.05rem 0;
    border-bottom: 1px solid var(--rule);
  }
  .contact-item:last-child { border-bottom: none; }
  .contact-item .label {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 0.76rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    color: var(--muted);
    flex: none;
    width: 8rem;
  }
  .contact-item .value { text-align: right; font-size: 0.98rem; }
  .contact-item .value .teach-title { display: block; }
  .contact-item .value .teach-faculty {
    display: block;
    color: var(--muted);
    font-size: 0.88rem;
    margin-top: 0.15rem;
  }
  .contact-item .value .teach-year {
    display: block;
    font-family: 'IBM Plex Mono', monospace;
    font-size: 0.8rem;
    color: var(--muted);
    margin-top: 0.2rem;
  }
  .contact-item a { text-decoration: none; border-bottom: 1px solid var(--rule); }

  /* Teaching rows: header (label + role) plus an arrow-toggled note */
  .teach-item { display: block; padding: 0; }
  .teach-head {
    width: 100%;
    display: flex;
    align-items: baseline;
    gap: 1.5rem;
    padding: 1.05rem 0;
    margin: 0;
    background: none;
    border: 0;
    font: inherit;
    color: inherit;
    text-align: left;
  }
  button.teach-head { cursor: pointer; }
  button.teach-head:hover .teach-title { color: var(--accent); }
  .teach-head .value { flex: 1; }
  .teach-arrow {
    flex: none;
    align-self: center;
    color: var(--muted);
    transition: transform 0.18s ease;
  }
  .teach-arrow::before { content: "\203A"; font-size: 1.1rem; }
  button.teach-head[aria-expanded="true"] .teach-arrow { transform: rotate(90deg); }
  button.teach-head[aria-expanded="true"] .teach-arrow { color: var(--accent); }
  .teach-details {
    padding: 0 0 1.15rem;
    color: var(--ink);
    font-size: 0.92rem;
    line-height: 1.6;
  }
  .teach-details p { margin: 0 0 0.7rem; }
  .teach-details p:last-child { margin-bottom: 0; }
  .contact-item a:hover { border-bottom-color: var(--accent); }

  /* ---------- Footer ---------- */

  footer {
    max-width: 720px;
    margin: 4rem auto 0;
    padding: 1.6rem 1.75rem 3rem;
    border-top: 1px solid var(--rule);
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 1rem;
    font-size: 0.84rem;
    color: var(--muted);
  }
  footer a { color: var(--muted); }
  footer a:hover { color: var(--accent); }

  @media (max-width: 480px) {
    .pub { grid-template-columns: 1fr; gap: 0.3rem; }
    .pub-year { padding-top: 0; }
    .site-header { flex-direction: column; gap: 0.9rem; align-items: flex-start; }
    .contact-item { flex-direction: column; gap: 0.3rem; }
    .contact-item .value { text-align: left; }
    .teach-head { flex-wrap: wrap; gap: 0.3rem; position: relative; }
    .teach-head .value { flex-basis: 100%; text-align: left; }
    .teach-arrow { position: absolute; top: 1.05rem; right: 0; }
  }