:root {
        --canvas: #ffffff;
        --ink: #17202b;
        --muted: #5d6874;
        --line: #d7dbd4;
        --panel: #ffffff;
        --accent: #0757c7;
        --accent-soft: #e8f0fc;
        --max-width: 1180px;
      }

      * { box-sizing: border-box; }
      html { scroll-behavior: smooth; }
      body {
        margin: 0;
        background: var(--canvas);
        color: var(--ink);
        font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
        font-size: 16px;
        line-height: 1.58;
      }
      a { color: inherit; text-decoration-thickness: 1px; text-underline-offset: 3px; }
      a:hover { color: var(--accent); }
      .shell { width: min(calc(100% - 40px), var(--max-width)); margin: auto; }

      .site-header { border-bottom: 1px solid var(--line); background: var(--canvas); }
      .masthead { padding: 20px 0; }
      .nav { display: flex; flex-wrap: wrap; gap: 10px 28px; }
      .nav a { color: var(--muted); font-size: 14px; text-decoration: none; white-space: nowrap; }
      .nav a:hover { color: var(--accent); }
      .nav a[aria-current="page"] { color: var(--accent); font-weight: 700; }

      main { padding: 76px 0 96px; }
      .eyebrow { margin: 0 0 15px; color: var(--accent); font-size: 12px; font-weight: 800; letter-spacing: .1em; text-transform: uppercase; }
      .intro { display: grid; grid-template-columns: minmax(0, 1.7fr) minmax(250px, .8fr); align-items: start; gap: clamp(36px, 8vw, 110px); padding-bottom: 48px; border-bottom: 1px solid var(--line); }
      h1, h2, h3, p { margin-top: 0; }
      h1 { max-width: 760px; margin-bottom: 22px; font-size: clamp(36px, 4.5vw, 58px); letter-spacing: -.05em; line-height: 1.12; }
      .credentials { font-size: .55em; letter-spacing: -.025em; white-space: nowrap; }
      .intro-bio { margin-top: 26px; color: #384451; }
      .intro-bio p { margin-bottom: 16px; }
      .intro-bio p:last-child { margin-bottom: 0; }
      .intro-bio a { text-decoration-color: var(--line); }
      .profile-photo { display: block; width: 100%; max-width: 300px; height: auto; aspect-ratio: 1408 / 1766; object-fit: cover; object-position: center; justify-self: end; border-radius: 4px; }
      .contact-links { display: flex; align-items: center; flex-wrap: wrap; gap: 8px; }
      .contact-icon { display: inline-flex; align-items: center; justify-content: center; width: 44px; height: 44px; color: var(--ink); border: 1px solid var(--line); border-radius: 50%; text-decoration: none; transition: color .15s, background .15s, border-color .15s; }
      .contact-icon:hover { color: var(--accent); background: var(--accent-soft); border-color: var(--accent); }
      .contact-icon:focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; }
      .contact-icon svg { width: 20px; height: 20px; }
      .contact-links .button { margin-left: 8px; }
      .button { display: inline-flex; align-items: center; justify-content: center; min-height: 43px; padding: 0 16px; border: 1px solid var(--accent); background: var(--accent); color: #fff !important; font-size: 14px; font-weight: 750; text-decoration: none; }
      .button:hover { background: #03459e; }

      .research-focus { padding-top: 40px; }
      h2 { margin-bottom: 18px; font-size: 23px; letter-spacing: -.03em; }
      h3 { margin-bottom: 8px; font-size: 16px; letter-spacing: -.015em; }
      .research-list { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 28px; padding: 0; margin: 0; list-style: none; }
      .research-list li { padding: 17px 0 18px; border-top: 1px solid var(--line); }
      .research-list h3::before { content: "↗"; display: inline-block; width: 24px; color: var(--accent); }
      .research-list h3 { margin: 0; }
      .research-list p { margin: 5px 0 0 24px; color: var(--muted); font-size: 14px; }

      .timeline { margin: 0; padding: 0; list-style: none; border-top: 1px solid var(--line); }
      .timeline > li { display: grid; grid-template-columns: 216px minmax(0, 1fr); gap: 32px; align-items: center; padding: 22px 0; border-bottom: 1px solid var(--line); }
      .brand-tile { display: flex; align-items: center; justify-content: center; padding: 0; background: var(--panel); }
      .brand-logo { display: block; width: 100%; height: auto; object-fit: contain; }
      .brand-link { display: block; width: 100%; }
      .brand-tile:focus-visible, .brand-link:focus-visible, .timeline a:focus-visible { outline: 2px solid var(--accent); outline-offset: 5px; }
      .timeline a { text-decoration-color: var(--line); }
      .timeline a:hover { text-decoration-color: var(--accent); }
      .school-logo-snu { max-width: 156px; }
      .brand-pair { flex-direction: column; gap: 10px; }
      /* The source image has a thin outer border; clip only that edge. */
      .harvard-logo { clip-path: inset(1px); }
      .timeline h3 { margin: 0; }
      .timeline p { margin: 4px 0 0; color: var(--muted); font-size: 14px; }
      /* Experience rows: role and dates together, then affiliation and research summary. */
      .experience-list > li { grid-template-columns: 216px minmax(0, 1fr); align-items: start; padding: 26px 0; }
      .experience-list .brand-tile { align-self: center; grid-row: auto; }
      .experience-list .brand-pair { gap: 14px; }
      .experience-details { min-width: 0; }
      .experience-details h3 { font-size: 18px; line-height: 1.4; }
      .role-qualifier { display: inline-block; margin-left: 8px; color: var(--muted); font-size: 12px; font-weight: 400; letter-spacing: 0; white-space: nowrap; }
      .timeline .experience-affiliation { margin-top: 8px; color: #384451; line-height: 1.6; }
      .timeline .experience-summary { margin-top: 10px; max-width: 72ch; line-height: 1.65; }
      .timeline time, .career-period { color: var(--muted); font-size: 13px; font-variant-numeric: tabular-nums; text-align: right; }
      .career-period { display: inline-block; margin-left: 8px; font-weight: 400; letter-spacing: 0; white-space: nowrap; }
      .experience-list > li:last-child { border-bottom: 0; }

      .section { margin-top: 72px; }
      .section.education-section { margin-top: 24px; padding-top: 10px; border-top: 2px solid #aeb7c1; }
      .education-section .timeline { border-top: 0; }
      .section-heading { display: flex; align-items: baseline; justify-content: space-between; gap: 16px; margin-bottom: 20px; }
      .section-heading h2 { margin: 0; }
      .section-heading a { color: var(--accent); font-size: 14px; font-weight: 700; }
      .paper-list { margin: 0; padding: 0; list-style: none; border-top: 1px solid var(--line); }
      .paper-list li { display: grid; grid-template-columns: 70px 1fr auto; gap: 16px; padding: 17px 0; border-bottom: 1px solid var(--line); }
      .paper-year { color: var(--muted); font-size: 14px; font-variant-numeric: tabular-nums; }
      .paper-title { margin: 0; font-weight: 700; }
      .paper-meta { margin: 4px 0 0; color: var(--muted); font-size: 14px; }
      .paper-link { color: var(--accent); font-size: 14px; font-weight: 750; white-space: nowrap; }

      footer { padding: 23px 0 34px; border-top: 1px solid var(--line); color: var(--muted); font-size: 13px; }
      .footer-inner { display: flex; align-items: center; justify-content: flex-end; }
      .footer-links { gap: 4px; }
      .footer-links .contact-icon { color: var(--muted); border-color: transparent; }
      .footer-links .contact-icon:hover { color: var(--accent); border-color: var(--accent-soft); }

      @media (max-width: 760px) {
        .shell { width: min(calc(100% - 32px), var(--max-width)); }
        .masthead { display: block; padding: 18px 0; }
        .nav { gap: 10px 20px; }
        main { padding: 52px 0 64px; }
        .intro { grid-template-columns: 1fr; }
        .intro { gap: 32px; padding-bottom: 46px; }
        .profile-photo { grid-row: 1; justify-self: start; width: 180px; }
        .research-focus { padding-top: 32px; }
        .research-list { grid-template-columns: 1fr; gap: 0; }
        .section { margin-top: 53px; }
        .paper-list li { grid-template-columns: 48px 1fr; gap: 10px; }
        .paper-link { grid-column: 2; }
        .timeline > li { grid-template-columns: 132px minmax(0, 1fr); gap: 12px 20px; }
        .brand-tile { grid-row: span 2; }
        .brand-pair { gap: 8px; }
        .timeline > li > time { grid-column: 2; text-align: left; }
        .footer-inner { flex-direction: column; align-items: flex-start; gap: 8px; }
      }
      @media (max-width: 420px) {
        .timeline > li { grid-template-columns: 1fr; gap: 14px; }
        .brand-tile { grid-row: auto; width: 200px; }
        .education-section .brand-tile { justify-content: flex-start; }
        .timeline > li > time { grid-column: 1; }
      }

/* Shared content pages. All records remain readable without JavaScript. */
[hidden] { display: none !important; }
:target { scroll-margin-top: 28px; }
a:focus-visible, button:focus-visible, input:focus-visible, select:focus-visible, summary:focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; }
.skip-link { position: absolute; left: 20px; top: -80px; padding: 12px 18px; background: var(--accent); color: white; z-index: 10; }
.skip-link:focus { top: 8px; }
.page-intro { max-width: 850px; margin-bottom: 44px; }
.page-intro h1 { margin-bottom: 18px; }
.lead { color: var(--muted); font-size: 19px; max-width: 70ch; }
.resource-links { display: flex; flex-wrap: wrap; gap: 8px 20px; margin-top: 14px; }
.resource-links a { color: var(--accent); font-size: 13px; font-weight: 650; overflow-wrap: anywhere; }
.category { display: block; color: var(--muted); font-size: 11px; font-weight: 650; letter-spacing: .06em; text-transform: uppercase; margin-bottom: 7px; }
.updates-list { list-style: none; padding: 0; margin: 0; border-top: 1px solid var(--line); }
.updates-list > li { padding: 30px 0; border-bottom: 1px solid var(--line); }

.updates-list h3 { font-size: 19px; line-height: 1.4; max-width: 85ch; }
.updates-list p { color: var(--muted); max-width: 85ch; margin-bottom: 0; font-size: 15px; }
.updates-list.compact > li { padding: 21px 0; }
.updates-list.compact h3 { font-size: 16px; margin-bottom: 0; }
.updates-list.compact h3 a { text-decoration: none; }
.updates-list.compact h3 a:hover { text-decoration: underline; }
.updates-list.compact .update-venue { margin: 8px 0 0; color: var(--accent); font-size: 13px; line-height: 1.5; }
.update-venue strong { font-weight: 650; }
.filter-bar { display: flex; flex-wrap: wrap; align-items: end; gap: 18px; padding: 20px; background: #f6f8fa; border: 1px solid #e5e8ed; border-radius: 4px; margin: 0 0 22px; }
.filter-bar label { display: flex; flex-direction: column; gap: 7px; font-size: 13px; font-weight: 650; }
.search-field { flex: 1 1 270px; }
input, select, button { font: inherit; }
input, select { border: 1px solid #bbc4cf; background: white; border-radius: 3px; padding: 10px 12px; color: var(--ink); min-height: 43px; max-width: 100%; }
input { width: 100%; }
button { padding: 10px 16px; min-height: 43px; border: 1px solid #bbc4cf; border-radius: 3px; background: white; cursor: pointer; font-size: 13px; }
button:hover { border-color: var(--accent); color: var(--accent); }
.result-count { color: var(--muted); font-size: 13px; }
.year-index { display: flex; flex-wrap: wrap; gap: 9px 18px; border-bottom: 1px solid var(--line); padding-bottom: 26px; margin-bottom: 35px; }
.year-index a { color: var(--accent); font-size: 14px; }
.publication-year { margin-bottom: 40px; }
.publication-jump { display: inline-block; margin-bottom: 24px; color: var(--accent); font-size: 14px; font-weight: 650; }
.publication-group:not([hidden]) + .publication-group { margin-top: 64px; padding-top: 32px; border-top: 2px solid var(--line); }

.publication-list { list-style: none; margin: 0; padding: 0; }
.publication-list > li { padding: 21px 0 24px; border-top: 1px solid var(--line); }
.publication-list h3, .publication-list h4 { margin: 0 0 8px; font-size: 18px; line-height: 1.42; letter-spacing: -.015em; }
.publication-list :is(h3, h4) a { text-decoration: none; }
.publication-list :is(h3, h4) a:hover { text-decoration: underline; }
.authors, .updates-list .authors { color: #4c5967; font-size: 14px; margin: 7px 0; }
.authors strong { color: var(--ink); font-weight: 700; }
.empty-state { padding: 40px 0; color: var(--muted); }
.project-grid { display: grid; grid-template-columns: repeat(2,minmax(0,1fr)); gap: 22px; }
.project-card { display: flex; flex-direction: column; padding: 28px; border: 1px solid var(--line); border-radius: 4px; }
.project-card h3 { font-size: 23px; line-height: 1.25; }
.project-card p:not(.eyebrow) { color: var(--muted); font-size: 15px; }
.project-card .resource-links { margin-top: auto; padding-top: 6px; }
.project-detail { display: grid; grid-template-columns: minmax(0, .9fr) minmax(0,1.1fr); gap: 42px; padding: 36px 0; border-top: 1px solid var(--line); }
.project-detail h3 { font-size: 23px; line-height: 1.3; }
.project-detail p { color: var(--muted); }
.project-figures img { width: 100%; height: auto; display: block; border-radius: 3px; margin-bottom: 16px; }
.funding { margin-top: 24px; font-size: 13px; color: var(--muted); }
.funding summary { cursor: pointer; color: var(--ink); }
.funding ul { padding-left: 20px; }
.funding li + li { margin-top: 12px; }
.section-note { color: var(--muted); font-size: 14px; }
.lab-intro { display: grid; grid-template-columns: minmax(0,1.7fr) minmax(0,1fr); gap: 60px; }
.lab-intro > div p { color: #384451; }
.archive-note { border-left: 2px solid var(--accent); padding-left: 24px; align-self: start; }
.archive-note p { font-size: 14px; color: var(--muted); margin: 10px 0 0; }
.people-grid { display: grid; grid-template-columns: repeat(3,minmax(0,1fr)); gap: 30px; }
.person { display: grid; grid-template-columns: 72px minmax(0,1fr); gap: 18px; border-top: 1px solid var(--line); padding-top: 22px; }
.person img { display: block; width: 72px; height: 90px; object-fit: cover; border-radius: 3px; }
.person h3 { font-size: 16px; }
.person-role { font-size: 14px; margin: 0; }
.person-detail { color: var(--muted); font-size: 13px; margin: 12px 0 0; }
.data-note { border-left: 2px solid var(--accent); padding-left: 24px; max-width: 85ch; margin-bottom: 40px; }
.data-note p { font-size: 14px; color: var(--muted); }
.dataset-list { list-style: none; padding: 0; margin: 0; }
.dataset-list > li { display: grid; grid-template-columns: 75px minmax(0,1fr); gap: 25px; border-top: 1px solid var(--line); padding: 27px 0; }
.dataset-list h2 { font-size: 19px; line-height: 1.4; margin-bottom: 8px; }
@media (max-width: 1000px) {
  .people-grid { grid-template-columns: repeat(2,minmax(0,1fr)); }
}
@media (max-width: 760px) {
  .lead { font-size: 17px; }
  .page-intro { margin-bottom: 32px; }
  .updates-list h3 { font-size: 17px; }
  .project-grid, .project-detail, .lab-intro { grid-template-columns: 1fr; }
  .project-detail { gap: 18px; }
  .project-card { padding: 24px; }
  .lab-intro { gap: 30px; }
  .filter-bar { padding: 16px; gap: 14px; }
  .filter-bar > label:not(.search-field) { flex: 1; }
  .dataset-list > li { grid-template-columns: 1fr; gap: 8px; }
}
@media (max-width: 480px) {
  .people-grid { grid-template-columns: 1fr; }
  .section-heading { align-items: start; }
  .section-heading > a { flex-shrink: 0; }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }
.updates-list > li { position: relative; }
.legacy-anchor { position: absolute; top: 0; }
.project-figures img { max-height: 400px; object-fit: contain; }

/* Teasers share one asset record across publications, updates, and Home. */
.visually-hidden { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; border: 0; }
.record-content, .record-text { min-width: 0; }
.record-content.with-teaser { display: grid; grid-template-columns: 320px minmax(0, 1fr); align-items: center; gap: 32px; }
.record-meta { display: flex; flex-wrap: wrap; align-items: baseline; gap: 10px; margin-bottom: 9px; color: var(--muted); font-size: 12px; }
.record-meta .category { display: inline; margin: 0; }
.record-meta time { font-variant-numeric: tabular-nums; }
.teaser { margin: 0; width: 100%; }
.teaser-link { display: block; width: 100%; border-radius: 4px; overflow: hidden; }
.teaser img { display: block; width: 100%; height: auto; max-height: 240px; object-fit: contain; }
.teaser-link:hover { opacity: .9; }
@media (max-width: 1000px) {
  .record-content.with-teaser { grid-template-columns: 280px minmax(0, 1fr); gap: 26px; }
}
@media (max-width: 700px) {
  .record-content.with-teaser { grid-template-columns: 1fr; gap: 20px; }
  .teaser { width: min(420px, 100%); }
  .teaser img { max-height: 280px; }
}
.teaser-gallery { display: grid; gap: 14px; min-width: 0; }
.feed-heading { flex-wrap: wrap; }
.section-actions { display: flex; flex-wrap: wrap; gap: 12px 22px; }