/* ==========================================================================
   Inyoung Oh — personal site
   Design tokens. Type: Sora (display) / Source Serif 4 (body) / IBM Plex Mono
   (labels, dates, metrics — the "metrology" voice of the site).
   ========================================================================== */

:root {
  --bg: #f5f7f8;
  --surface: #ffffff;
  --ink: #17222c;
  --muted: #5c6b77;
  --line: rgba(23, 34, 44, 0.12);
  --line-soft: rgba(23, 34, 44, 0.07);
  --accent: #0e639c;
  --accent-strong: #0a4f7e;
  --accent-soft: rgba(14, 99, 156, 0.09);
  --amber: #a16207;
  --amber-soft: rgba(161, 98, 7, 0.12);
  --shadow: 0 1px 2px rgba(23, 34, 44, 0.05), 0 8px 24px -12px rgba(23, 34, 44, 0.12);
  --radius: 12px;
  --font-display: "Sora", system-ui, sans-serif;
  --font-body: "Source Serif 4", Georgia, serif;
  --font-mono: "IBM Plex Mono", ui-monospace, monospace;
}

[data-theme="dark"] {
  --bg: #0d1319;
  --surface: #151d26;
  --ink: #e6edf3;
  --muted: #94a4b2;
  --line: rgba(230, 237, 243, 0.14);
  --line-soft: rgba(230, 237, 243, 0.08);
  --accent: #5cabde;
  --accent-strong: #82c0e8;
  --accent-soft: rgba(92, 171, 222, 0.13);
  --amber: #d9a441;
  --amber-soft: rgba(217, 164, 65, 0.16);
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.3), 0 8px 24px -12px rgba(0, 0, 0, 0.5);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 84px; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; animation: none !important; }
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 1.06rem;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  transition: background 0.25s ease, color 0.25s ease;
}

a { color: var(--accent); text-decoration-thickness: 1px; text-underline-offset: 2.5px; }
a:hover { color: var(--accent-strong); }

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

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 4px;
}

.wrap { max-width: 940px; margin: 0 auto; padding: 0 22px; }

/* ---------------- Nav ---------------- */

.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line-soft);
}
.nav-inner {
  display: flex;
  align-items: center;
  gap: 18px;
  height: 60px;
}
.nav-name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.98rem;
  letter-spacing: -0.01em;
  color: var(--ink);
  text-decoration: none;
  white-space: nowrap;
}
.nav-icons { display: flex; align-items: center; gap: 2px; margin-right: auto; }
.nav-icons a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 30px;
  height: 30px;
  border-radius: 8px;
  color: var(--muted);
}
.nav-icons a:hover { color: var(--accent); background: var(--accent-soft); }
.nav-icons svg { width: 16px; height: 16px; }
.nav-links { display: flex; align-items: center; gap: 4px; flex-wrap: wrap; }
.nav-links a {
  font-family: var(--font-display);
  font-size: 0.84rem;
  font-weight: 500;
  color: var(--muted);
  text-decoration: none;
  padding: 6px 10px;
  border-radius: 8px;
  white-space: nowrap;
}
.nav-links a:hover { color: var(--ink); background: var(--line-soft); }
.nav-links a.nav-cv { color: var(--accent); }
.nav-links a[aria-current="page"] { color: var(--ink); }

.theme-toggle {
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--muted);
  width: 34px;
  height: 34px;
  border-radius: 9px;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0;
}
.theme-toggle:hover { color: var(--ink); border-color: var(--muted); }
.theme-toggle svg { width: 16px; height: 16px; }
[data-theme="dark"] .icon-moon { display: none; }
:root:not([data-theme="dark"]) .icon-sun { display: none; }

/* ---------------- Shared section furniture ---------------- */

.eyebrow {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0 0 10px;
}

section { padding: 44px 0 8px; }
section > .wrap > h2 {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 0 0 6px;
}
.section-rule { border: 0; border-top: 1px solid var(--line-soft); margin: 40px 0 0; }

/* ---------------- Hero ---------------- */

.hero { padding: 56px 0 10px; }
.hero-grid {
  display: grid;
  grid-template-columns: 1fr 208px;
  gap: 40px;
  align-items: start;
}
.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2.1rem, 5.5vw, 2.9rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.08;
  margin: 0 0 14px;
}
.hero-thesis {
  font-size: 1.22rem;
  font-style: italic;
  line-height: 1.5;
  color: var(--ink);
  margin: 0 0 20px;
  max-width: 34em;
}
.hero-links { display: flex; flex-wrap: wrap; gap: 8px; }
.hero-links a, .btn {
  font-family: var(--font-display);
  font-size: 0.82rem;
  font-weight: 500;
  text-decoration: none;
  color: var(--ink);
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 7px 14px;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  transition: border-color 0.15s ease, background 0.15s ease;
}
.hero-links a:hover, .btn:hover { border-color: var(--accent); color: var(--accent-strong); }
.hero-links a.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}
.hero-links a.primary:hover { background: var(--accent-strong); color: #fff; }
[data-theme="dark"] .hero-links a.primary { color: #0d1319; }
.hero-links svg { width: 14px; height: 14px; flex: none; }

.hero-photo {
  width: 208px;
  aspect-ratio: 4 / 5;
  object-fit: cover;
  border-radius: 16px;
  border: 1px solid var(--line-soft);
  box-shadow: var(--shadow);
}

/* ---------------- Highlight banner ---------------- */

.highlight {
  margin: 34px 0 0;
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  background: var(--surface);
  border-radius: var(--radius);
  padding: 14px 18px;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 14px;
  box-shadow: var(--shadow);
}
.highlight .tag {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  color: var(--accent);
  background: var(--accent-soft);
  border-radius: 5px;
  padding: 3px 8px;
  white-space: nowrap;
}
.highlight p { margin: 0; font-size: 0.98rem; }

/* ---------------- Research narrative ---------------- */

.research p { margin: 0 0 1.05em; }
.research p a { color: inherit; text-decoration-color: var(--accent); }
.research p a:hover { color: var(--accent-strong); }

/* Diagram */
.diagram-card {
  margin: 26px 0 10px;
  background: var(--surface);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 20px 16px 12px;
  overflow-x: auto;
}
.diagram-card svg { display: block; width: 100%; height: auto; }
.diagram-card .svg-mobile { display: none; max-width: 460px; margin: 0 auto; }
@media (max-width: 640px) {
  .diagram-card .svg-desktop { display: none; }
  .diagram-card .svg-mobile { display: block; }
}

/* AI-artwork figure: stays a white plate in both themes, like a journal figure */
.diagram-figure { background: #ffffff; }
.diagram-figure img { display: block; width: 100%; height: auto; border-radius: 6px; }
.diagram-stage { position: relative; }
.diagram-labels { position: relative; height: 2.7em; margin-top: 4px; }
.diagram-labels > div { position: absolute; top: 0; transform: translateX(-50%); text-align: center; white-space: nowrap; }
.diagram-labels strong { display: block; font-family: var(--font-display); font-weight: 600; font-size: 0.82rem; letter-spacing: 0.03em; color: #17222c; }
.diagram-labels span { font-family: var(--font-mono); font-size: 0.66rem; color: #5c6b77; }
.diagram-figure .diagram-caption { color: #5c6b77; }
@media (max-width: 620px) {
  .diagram-labels { height: 1.5em; }
  .diagram-labels strong { font-size: 0.6rem; }
  .diagram-labels span { display: none; }
}
.diagram-caption {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--muted);
  text-align: center;
  margin: 8px 0 2px;
  letter-spacing: 0.04em;
}

/* Bio toggle */
.bio-details {
  margin-top: 18px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: var(--surface);
}
.bio-details summary {
  cursor: pointer;
  list-style: none;
  font-family: var(--font-display);
  font-size: 0.86rem;
  font-weight: 500;
  color: var(--muted);
  padding: 12px 18px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.bio-details summary::-webkit-details-marker { display: none; }
.bio-details summary::before { content: "+"; font-family: var(--font-mono); color: var(--accent); }
.bio-details[open] summary::before { content: "\2212"; }
.bio-details summary:hover { color: var(--ink); }
.bio-body { padding: 0 18px 16px; }
.bio-body p { margin: 0 0 12px; font-size: 0.99rem; }
.copy-btn {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  color: var(--accent);
  background: var(--accent-soft);
  border: 0;
  border-radius: 7px;
  padding: 6px 12px;
  cursor: pointer;
}
.copy-btn:hover { background: var(--accent); color: #fff; }
[data-theme="dark"] .copy-btn:hover { color: #0d1319; }

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

.pub-list { display: flex; flex-direction: column; gap: 14px; margin-top: 18px; }

.pub-card {
  display: grid;
  grid-template-columns: 176px 1fr;
  gap: 18px;
  background: var(--surface);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  padding: 16px;
  box-shadow: var(--shadow);
  scroll-margin-top: 90px;
}
.pub-card.no-thumb { grid-template-columns: 1fr; }
.pub-card:target { border-color: var(--accent); }

.pub-thumb {
  width: 176px;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border-radius: 8px;
  border: 1px solid var(--line-soft);
  background: var(--bg);
}
.pub-title {
  font-family: var(--font-display);
  font-size: 1.02rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  line-height: 1.35;
  margin: 0 0 5px;
}
.pub-authors { font-size: 0.92rem; color: var(--muted); margin: 0 0 3px; }
.me { color: var(--ink); font-weight: 600; text-decoration: underline; text-decoration-color: var(--accent); text-underline-offset: 3px; }
.pub-venue { font-size: 0.92rem; font-style: italic; color: var(--muted); margin: 0 0 9px; }
.pub-venue .year { font-family: var(--font-mono); font-style: normal; font-size: 0.8rem; }

.badge {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 500;
  letter-spacing: 0.06em;
  border-radius: 5px;
  padding: 2.5px 8px;
  margin: 0 6px 6px 0;
  vertical-align: middle;
}
.badge.award { color: var(--amber); background: var(--amber-soft); }
.badge.status { color: var(--accent); background: var(--accent-soft); }

.pub-actions { display: flex; flex-wrap: wrap; gap: 7px; }
.pub-actions a, .pub-actions button {
  font-family: var(--font-display);
  font-size: 0.76rem;
  font-weight: 500;
  color: var(--accent);
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 7px;
  padding: 4.5px 11px;
  text-decoration: none;
  cursor: pointer;
}
.pub-actions a:hover, .pub-actions button:hover { border-color: var(--accent); background: var(--accent-soft); }

.pub-abs, .pub-bib {
  grid-column: 1 / -1;
  margin: 4px 0 0;
  border-top: 1px dashed var(--line);
  padding-top: 12px;
  font-size: 0.94rem;
  color: var(--muted);
}
.pub-abs[hidden], .pub-bib[hidden] { display: none; }
.pub-bib pre {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  line-height: 1.55;
  background: var(--bg);
  border: 1px solid var(--line-soft);
  border-radius: 8px;
  padding: 12px 14px;
  overflow-x: auto;
  margin: 0 0 8px;
  white-space: pre-wrap;
  word-break: break-word;
}

.see-all { margin-top: 20px; font-family: var(--font-display); font-size: 0.9rem; }

/* Compact rows (domestic / patents) */
.pub-row {
  padding: 13px 2px;
  border-bottom: 1px solid var(--line-soft);
}
.pub-row .pub-title { font-size: 0.96rem; }
.pub-row .pub-venue { margin-bottom: 0; }

/* Filters */
.filters { display: flex; flex-wrap: wrap; gap: 8px; margin: 20px 0 4px; }
.chip {
  font-family: var(--font-display);
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--muted);
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 6px 14px;
  cursor: pointer;
}
.chip:hover { color: var(--ink); border-color: var(--muted); }
.chip.active {
  color: #fff;
  background: var(--accent);
  border-color: var(--accent);
}
[data-theme="dark"] .chip.active { color: #0d1319; }

.pub-section-title {
  font-family: var(--font-display);
  font-size: 1.14rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin: 34px 0 4px;
  display: flex;
  align-items: baseline;
  gap: 10px;
}
.pub-section-title .count {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  font-weight: 400;
  color: var(--muted);
}

/* ---------------- News ---------------- */

.news-list { list-style: none; margin: 16px 0 0; padding: 0; }
.news-list li {
  display: grid;
  grid-template-columns: 108px 1fr;
  gap: 16px;
  padding: 10px 0;
  border-bottom: 1px solid var(--line-soft);
  font-size: 0.98rem;
}
.news-list .date {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--muted);
  padding-top: 3px;
  white-space: nowrap;
}
.news-list li.hidden-news { display: none; }
.news-more { margin-top: 14px; }

/* ---------------- Experience / Education ---------------- */

.xp-card {
  background: var(--surface);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 18px 20px;
  margin-top: 16px;
}
.xp-head { display: flex; flex-wrap: wrap; align-items: baseline; gap: 4px 12px; }
.xp-role { font-family: var(--font-display); font-weight: 600; font-size: 1.02rem; letter-spacing: -0.01em; }
.xp-org { color: var(--muted); font-size: 0.95rem; }
.xp-date { font-family: var(--font-mono); font-size: 0.76rem; color: var(--muted); margin-left: auto; white-space: nowrap; }
.xp-card ul { margin: 10px 0 0; padding-left: 1.2em; }
.xp-card li { margin: 6px 0; font-size: 0.97rem; }
.xp-note { font-size: 0.93rem; font-style: italic; color: var(--muted); margin: 8px 0 0; }
.xp-sub {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 14px 0 2px;
}

.edu-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin-top: 16px; }
.edu-grid .xp-card { margin-top: 0; }
.edu-thesis { font-size: 0.88rem; color: var(--muted); margin: 8px 0 0; }

/* Awards */
.award-table { width: 100%; border-collapse: collapse; margin-top: 14px; }
.award-table td { padding: 9px 0; border-bottom: 1px solid var(--line-soft); font-size: 0.97rem; vertical-align: top; }
.award-table td.yr { font-family: var(--font-mono); font-size: 0.78rem; color: var(--muted); text-align: right; white-space: nowrap; padding-left: 16px; }

/* Misc grid (teaching / service / skills) */
.misc-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin-top: 16px; }
.misc-grid h3 {
  font-family: var(--font-display);
  font-size: 0.94rem;
  font-weight: 600;
  margin: 0 0 8px;
}
.misc-grid p, .misc-grid li { font-size: 0.94rem; margin: 0 0 8px; }
.misc-grid ul { margin: 0; padding-left: 1.15em; }

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

footer { margin-top: 56px; border-top: 1px solid var(--line-soft); padding: 30px 0 44px; }
.foot-grid { display: flex; flex-wrap: wrap; gap: 10px 26px; align-items: baseline; }
.foot-grid a { font-size: 0.9rem; }
.foot-meta {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--muted);
  margin-top: 14px;
}

/* ---------------- 404 ---------------- */
.err { text-align: center; padding: 110px 0 60px; }
.err h1 { font-family: var(--font-mono); font-size: 3rem; margin: 0 0 8px; color: var(--accent); }

/* ---------------- Responsive ---------------- */

@media (max-width: 760px) {
  .nav-inner { gap: 8px; }
  .nav-links a { padding: 6px 7px; }
  .hero-grid { grid-template-columns: 1fr; gap: 24px; }
  .hero-photo { width: 148px; }
  .pub-card { grid-template-columns: 1fr; }
  .pub-thumb { width: 100%; max-width: 340px; }
  .edu-grid, .misc-grid { grid-template-columns: 1fr; }
  .news-list li { grid-template-columns: 1fr; gap: 2px; }
  .nav-links a:not(.nav-cv):not(.nav-pubs) { display: none; }
}

@media (max-width: 460px) {
  .nav-name { display: none; }
}

@media print {
  .nav, .theme-toggle, .hero-links, .pub-actions, .filters, .news-more { display: none !important; }
  body { background: #fff; color: #000; }
}