/* Shared styles — Kitae Kim personal site (DM Serif Display direction) */

:root {
  --bg: #dee2ea;
  --card: #eef1f6;
  --ink: #0a0e18;
  --ink-2: #4f5670;
  --rule: rgba(10, 14, 24, 0.14);
  --cobalt: #1f3ed6;
  --cobalt-deep: #0a1a7a;
  --cobalt-ink: #ffffff;
  --cobalt-soft: rgba(31, 62, 214, 0.08);

  --display: "DM Serif Display", "Fraunces", Georgia, serif;
  --body: "Geist", "Inter", system-ui, sans-serif;
  --mono: "Geist Mono", ui-monospace, "SF Mono", Menlo, monospace;

  --max: 1120px;
  --pad: 40px;
}

html[data-theme="dark"] {
  --bg: #0a0d14;
  --card: #131723;
  --ink: #eef1f7;
  --ink-2: #8a93a8;
  --rule: rgba(238, 241, 247, 0.10);
  --cobalt: #5b8cff;
  --cobalt-deep: #4a73d9;
  --cobalt-ink: #0a0d14;
  --cobalt-soft: rgba(91, 140, 255, 0.10);
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  background: var(--bg);
  color: var(--ink);
  font-family: var(--body);
  font-size: 16px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background 0.2s ease, color 0.2s ease;
}
a { color: inherit; }
a.accent { color: var(--cobalt); text-decoration: underline; text-underline-offset: 3px; }
h1, h2, h3 { font-family: var(--display); font-weight: 400; letter-spacing: -0.02em; }
h1 { font-size: clamp(56px, 7.5vw, 104px); line-height: 0.95; margin: 0; }
h2 { font-size: 40px; line-height: 1.05; margin: 0; letter-spacing: -0.03em; }
h3 { font-size: 24px; line-height: 1.2; margin: 0; }

p { text-wrap: pretty; }

/* Nav chrome */
.topbar {
  position: sticky; top: 0; z-index: 40;
  background: color-mix(in oklab, var(--bg) 85%, transparent);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--rule);
}
.topbar-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 14px var(--pad);
  display: flex; justify-content: space-between; align-items: center;
  gap: 16px;
}
.brand {
  display: flex; align-items: center; gap: 10px;
  font-family: var(--mono);
  font-size: 12px; letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--ink-2);
  text-decoration: none;
}
.brand-dot { width: 8px; height: 8px; background: var(--cobalt); border-radius: 1px; }
.nav-links {
  display: flex; gap: 4px; align-items: center; flex-wrap: wrap;
  font-family: var(--mono);
  font-size: 12px; letter-spacing: 0.04em;
}
.nav-links a {
  text-decoration: none;
  padding: 8px 12px; border-radius: 4px;
  color: var(--ink-2);
  transition: all 0.15s ease;
}
.nav-links a:hover { color: var(--ink); background: var(--cobalt-soft); }
.nav-links a.active { color: var(--cobalt); }

.controls {
  display: flex; gap: 6px; align-items: center;
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.04em;
}
.ctrl-btn {
  border: 1px solid var(--rule); background: transparent; color: var(--ink-2);
  padding: 7px 10px; border-radius: 4px; cursor: pointer;
  font: inherit; letter-spacing: 0.04em;
  transition: all 0.15s ease;
  display: inline-flex; align-items: center; gap: 6px;
}
.ctrl-btn:hover { background: var(--card); color: var(--ink); border-color: var(--ink-2); }
.ctrl-btn.active { color: var(--cobalt); border-color: var(--cobalt); background: var(--cobalt-soft); }
.ctrl-group { display: inline-flex; border: 1px solid var(--rule); border-radius: 4px; overflow: hidden; }
.ctrl-group .ctrl-btn { border: none; border-radius: 0; }
.ctrl-group .ctrl-btn + .ctrl-btn { border-left: 1px solid var(--rule); }

/* Sidebar variant */
.sidebar {
  position: fixed; top: 0; left: 0; bottom: 0;
  width: 240px; padding: 40px 28px;
  display: flex; flex-direction: column; gap: 28px;
  border-right: 1px solid var(--rule);
  background: var(--bg);
  z-index: 40;
}
.sidebar .brand { font-size: 11px; }
.sidebar .side-name {
  font-family: var(--display); font-size: 30px; line-height: 1; letter-spacing: -0.02em;
  color: var(--ink); margin-top: 6px;
}
.sidebar .side-role {
  font-family: var(--body); font-size: 13px; color: var(--ink-2); line-height: 1.5;
}
.sidebar .nav-links { flex-direction: column; gap: 2px; align-items: stretch; }
.sidebar .nav-links a { padding: 8px 10px; }
.sidebar-layout { margin-left: 240px; }
@media (max-width: 900px) {
  .sidebar { position: static; width: auto; border-right: none; border-bottom: 1px solid var(--rule); padding: 24px var(--pad); }
  .sidebar .nav-links { flex-direction: row; flex-wrap: wrap; }
  .sidebar-layout { margin-left: 0; }
}

/* Minimal nav variant */
.minimal-top {
  max-width: var(--max);
  margin: 0 auto;
  padding: 32px var(--pad) 0;
  display: flex; justify-content: space-between; align-items: baseline;
  gap: 16px; flex-wrap: wrap;
}
.minimal-top .brand { font-size: 12px; }

/* Page container */
.container { max-width: var(--max); margin: 0 auto; padding: 0 var(--pad); }
.page { padding-top: 56px; padding-bottom: 120px; }
.section { padding: 72px 0 8px; scroll-margin-top: 80px; }
.section + .section { border-top: 1px solid var(--rule); margin-top: 0; }
.section-head {
  display: flex; align-items: baseline; gap: 20px; margin-bottom: 36px;
}
.section-num {
  font-family: var(--mono); font-size: 12px; letter-spacing: 0.15em;
  color: var(--cobalt); font-weight: 500;
}

/* Hero */
.hero { padding-top: 56px; padding-bottom: 72px; }
.hero-grid {
  display: grid; grid-template-columns: 360px 1fr; gap: 48px;
  align-items: stretch;
}
@media (max-width: 760px) {
  .hero-grid { grid-template-columns: 1fr; }
  .hero-portrait { aspect-ratio: 4/3 !important; }
}
.hero-topline {
  display: flex; justify-content: space-between; align-items: baseline;
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--ink-2);
  margin-bottom: 28px;
}
.hero-portrait {
  width: 100%; aspect-ratio: 4/5;
  background: var(--ink);
  border-radius: 4px; position: relative; overflow: hidden; color: #fff;
}
.hero-portrait-img {
  position: absolute; inset: 0;
  width: 100%; height: 100%;
  object-fit: cover;
  object-position: 50% 42%;
  display: block;
}
.hero-portrait::after {
  content: ""; position: absolute; inset: 0;
  background:
    linear-gradient(180deg, rgba(0,0,0,0.45) 0%, rgba(0,0,0,0) 22%, rgba(0,0,0,0) 78%, rgba(0,0,0,0.35) 100%);
  pointer-events: none;
}
.hero-portrait-caption {
  position: absolute; top: 20px; left: 22px; right: 22px;
  display: flex; justify-content: space-between;
  font-family: var(--mono); font-size: 10px; letter-spacing: 0.18em;
  text-transform: uppercase; opacity: 0.85;
}
.hero-portrait-note {
  position: absolute; bottom: 22px; left: 22px; right: 22px;
  font-family: var(--display); font-size: 20px; line-height: 1.2; letter-spacing: -0.01em;
}
.hero-text { display: flex; flex-direction: column; justify-content: space-between; gap: 28px; }
.hero-name .accent-word { color: var(--cobalt); }
.hero-tagline { font-size: 19px; line-height: 1.45; margin: 24px 0 0; color: var(--ink); max-width: 520px; }
.status-card {
  background: var(--card); padding: 18px 20px; border: 1px solid var(--rule);
  border-radius: 4px; font-family: var(--mono); font-size: 12px; line-height: 1.7;
}
.status-row { display: grid; grid-template-columns: 84px 1fr; gap: 10px; margin-bottom: 4px; }
.status-row .label { color: var(--cobalt); font-weight: 500; }

/* About */
.about-grid { display: grid; grid-template-columns: 2fr 1fr; gap: 48px; align-items: start; }
@media (max-width: 760px) { .about-grid { grid-template-columns: 1fr; } }
.about p { font-size: 18px; line-height: 1.6; margin: 0 0 16px; }
.interests-card {
  background: var(--card); padding: 22px 24px; border: 1px solid var(--rule); border-radius: 4px;
}
.interests-card .label {
  font-family: var(--mono); font-size: 10px; letter-spacing: 0.18em; text-transform: uppercase;
  color: var(--cobalt); margin-bottom: 14px; font-weight: 500;
}
.interests-card .item {
  font-family: var(--display); font-size: 18px; line-height: 1.4;
  padding: 12px 0; border-bottom: 1px solid var(--rule);
}
.interests-card .item:last-child { border-bottom: none; }

/* News */
.news-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px; }
@media (max-width: 760px) { .news-grid { grid-template-columns: 1fr; } }
.news-item {
  background: var(--card); color: var(--ink);
  padding: 20px 22px; border: 1px solid var(--rule); border-radius: 4px;
  display: flex; flex-direction: column; gap: 10px;
}
.news-item.hero {
  background: var(--cobalt); color: var(--cobalt-ink); border: none;
}
.news-item .date {
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.12em;
  text-transform: uppercase; font-weight: 500; color: var(--cobalt);
}
.news-item.hero .date { color: var(--cobalt-ink); opacity: 0.85; }
.news-item .body { font-size: 16px; line-height: 1.45; }

/* Publications */
.pub-list { list-style: none; padding: 0; margin: 0; }
.pub {
  padding: 28px 0; border-top: 1px solid var(--rule);
  display: grid; grid-template-columns: 72px 1fr 200px; gap: 32px; align-items: start;
}
.pub:first-child { border-top: none; padding-top: 0; }
.pub:last-child { border-bottom: none; padding-bottom: 0; }
/* Publication section: suppress the global .section + .section divider since pub rows already provide structure */
#publications + .section { border-top: none; }
@media (max-width: 760px) { .pub { grid-template-columns: 1fr; gap: 14px; } }
.pub .num {
  font-family: var(--display); font-size: 56px; font-weight: 400;
  color: var(--cobalt); line-height: 0.9; letter-spacing: -0.04em;
}
.pub-title {
  font-family: var(--display); font-size: 26px; line-height: 1.25;
  margin: 0 0 8px; text-wrap: pretty;
}
.pub-title a { color: inherit; text-decoration: none; transition: color 0.15s ease; }
.pub-title a:hover { color: var(--cobalt); }
.pub-authors { font-size: 14px; color: var(--ink-2); margin-bottom: 10px; }
.pub-authors .me { color: var(--ink); font-weight: 600; text-decoration: none; }
.pub-meta { display: flex; flex-direction: column; gap: 4px; }
.pub-venue {
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.1em;
  text-transform: uppercase; color: var(--ink); font-weight: 500;
}
.pub-venue-note { font-family: var(--mono); font-size: 10px; color: var(--ink-2); }
.pub-detail-link {
  display: inline-block; margin-top: 10px;
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.08em;
  color: var(--cobalt); text-decoration: none;
  padding: 6px 10px; border: 1px solid var(--cobalt); border-radius: 3px;
  transition: all 0.15s ease;
}
.pub-detail-link:hover { background: var(--cobalt); color: var(--cobalt-ink); }

/* Publication abstract toggle — SVG plus → minus transition */
.pub-toggle {
  margin-top: 16px;
  background: transparent;
  padding: 6px; margin-left: -6px;
  border: 0; cursor: pointer;
  display: inline-flex; align-items: center; justify-content: center;
  color: var(--ink-2);
  transition: color 0.2s ease;
  -webkit-tap-highlight-color: transparent;
}
.pub-toggle-glyph { display: block; overflow: visible; }
.pub-toggle-glyph .bar-h,
.pub-toggle-glyph .bar-v {
  transform-origin: 8px 8px;
  transition: transform 0.28s cubic-bezier(.4,.1,.2,1);
}
.pub-toggle:hover { color: var(--cobalt); }
.pub-toggle:hover .pub-toggle-glyph .bar-h { transform: scaleX(1.25); }
.pub-toggle[aria-expanded="true"] { color: var(--cobalt); }
.pub-toggle[aria-expanded="true"] .pub-toggle-glyph .bar-v { transform: scaleY(0); }
.pub-toggle[aria-expanded="true"] .pub-toggle-glyph .bar-h { transform: scaleX(1.25); }
.pub-toggle-icon, .pub-toggle-label { display: none !important; }

.pub-abstract {
  margin-top: 18px; padding-left: 16px;
  border-left: 2px solid var(--cobalt);
  animation: abstract-in 0.22s ease-out;
}
@keyframes abstract-in {
  from { opacity: 0; transform: translateY(-4px); }
  to   { opacity: 1; transform: translateY(0); }
}
.pub-abstract p {
  margin: 0 0 18px; font-size: 15.5px; line-height: 1.65;
  color: var(--ink); text-wrap: pretty; max-width: 640px;
}

/* Abstract actions — plain text links with subtle hierarchy */
.pub-actions {
  display: flex; gap: 20px; align-items: center; flex-wrap: wrap;
  font-family: var(--body); font-size: 13px;
}
.pub-action {
  color: var(--ink); text-decoration: none;
  font-weight: 500;
  border-bottom: 1px solid var(--ink);
  padding-bottom: 1px;
  transition: color 0.15s ease, border-color 0.15s ease;
  background: none; border-top: 0; border-left: 0; border-right: 0;
  cursor: pointer; font-family: inherit; font-size: inherit;
  padding-left: 0; padding-right: 0;
}
.pub-action:hover { color: var(--cobalt); border-color: var(--cobalt); }
.pub-action--primary { color: var(--cobalt); border-color: var(--cobalt); }
.pub-action--primary:hover { color: var(--cobalt-deep); border-color: var(--cobalt-deep); }
.pub-action--disabled {
  color: var(--ink-2); border-color: transparent; cursor: default;
  font-style: italic;
}
.pub-action--disabled:hover { color: var(--ink-2); border-color: transparent; }

/* Experience */
.exp-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
@media (max-width: 760px) { .exp-grid { grid-template-columns: 1fr; } }
.exp-card {
  background: var(--card); padding: 22px 24px; border: 1px solid var(--rule); border-radius: 4px;
}
.exp-card .date {
  font-family: var(--mono); font-size: 11px; color: var(--cobalt);
  letter-spacing: 0.08em; margin-bottom: 12px; font-weight: 500;
}
.exp-card .org {
  font-family: var(--display); font-size: 24px; margin-bottom: 4px; line-height: 1.2;
}
.exp-card .role { font-size: 14px; color: var(--ink-2); margin-bottom: 12px; }
.exp-card .desc { font-size: 14px; line-height: 1.6; color: var(--ink); }

/* Contact */
.contact {
  margin-top: 40px;
  padding: 56px 48px;
  background: var(--cobalt); color: var(--cobalt-ink);
  border-radius: 4px;
}
.contact .label {
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.2em;
  text-transform: uppercase; opacity: 0.85; margin-bottom: 18px;
}
.contact .headline {
  font-family: var(--display); font-size: 52px; line-height: 1.1;
  margin: 0 0 36px; letter-spacing: -0.03em;
}
.contact-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; }
@media (max-width: 760px) { .contact-grid { grid-template-columns: repeat(2, 1fr); } .contact { padding: 40px 28px; } .contact .headline { font-size: 34px; } }
.contact-link {
  font-family: var(--mono); font-size: 12px; letter-spacing: 0.04em;
  color: var(--cobalt-ink); text-decoration: none;
  padding: 14px 16px; border: 1px solid var(--cobalt-ink); border-radius: 3px;
  display: flex; justify-content: space-between; align-items: center;
  transition: all 0.15s ease; cursor: pointer;
  background: transparent;
  font: inherit;
}
.contact-link span:first-child { text-transform: uppercase; opacity: 0.75; }
.contact-link:hover { background: var(--cobalt-ink); color: var(--cobalt); }
.contact-link.copied span:first-child { opacity: 1; }
.contact-link.copied::after { content: "✓ Copied"; position: absolute; }

/* Footer */
.footer {
  border-top: 1px solid var(--rule);
  padding: 32px 0 40px; margin-top: 64px;
  font-family: var(--mono); font-size: 11px; color: var(--ink-2);
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px;
}

/* Back to top */
.back-to-top {
  position: fixed; right: 24px; bottom: 24px; z-index: 50;
  width: 44px; height: 44px; border-radius: 50%;
  background: var(--ink); color: var(--bg);
  border: none; cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  font-family: var(--mono); font-size: 18px;
  box-shadow: 0 4px 16px rgba(0,0,0,0.15);
  opacity: 0; pointer-events: none;
  transform: translateY(8px);
  transition: all 0.25s ease;
}
.back-to-top.visible { opacity: 1; pointer-events: auto; transform: translateY(0); }
.back-to-top:hover { background: var(--cobalt); color: var(--cobalt-ink); }

/* Publication detail */
.pub-detail .back-link {
  font-family: var(--mono); font-size: 12px; letter-spacing: 0.06em;
  color: var(--cobalt); text-decoration: none; display: inline-flex; align-items: center; gap: 6px;
  margin-bottom: 40px;
}
.pub-detail .back-link:hover { text-decoration: underline; text-underline-offset: 3px; }
.pub-detail h1 {
  font-size: clamp(36px, 5vw, 56px); line-height: 1.05; margin: 0 0 20px;
  letter-spacing: -0.02em;
}
.pub-detail .meta-row {
  display: flex; gap: 20px; flex-wrap: wrap;
  font-family: var(--mono); font-size: 12px; letter-spacing: 0.08em;
  color: var(--ink-2); margin-bottom: 32px;
}
.pub-detail .meta-row .venue { color: var(--cobalt); font-weight: 500; }
.pub-detail .body-text { font-size: 18px; line-height: 1.6; max-width: 700px; color: var(--ink); }
.pub-detail .body-text p { margin: 0 0 16px; }
.pub-detail .download-row {
  display: flex; gap: 12px; margin-top: 32px; flex-wrap: wrap;
}

/* Utility */
.hidden-lang { display: none; }
html[data-lang="en"] .lang-kr, html[data-lang="kr"] .lang-en { display: none; }

/* Variation-selector home */
.hub { min-height: 100vh; padding: 80px var(--pad); max-width: 1000px; margin: 0 auto; }
.hub h1 { font-size: clamp(48px, 6vw, 88px); margin-bottom: 20px; }
.hub-intro { font-size: 18px; color: var(--ink-2); max-width: 640px; margin-bottom: 48px; }
.hub-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 16px; }
.hub-card {
  background: var(--card); border: 1px solid var(--rule); border-radius: 6px;
  padding: 28px 24px; text-decoration: none; color: inherit;
  transition: all 0.2s ease; display: flex; flex-direction: column; gap: 10px;
}
.hub-card:hover { transform: translateY(-2px); border-color: var(--cobalt); }
.hub-card .label { font-family: var(--mono); font-size: 10px; letter-spacing: 0.2em; text-transform: uppercase; color: var(--cobalt); }
.hub-card .name { font-family: var(--display); font-size: 26px; line-height: 1.2; }
.hub-card .desc { font-size: 14px; color: var(--ink-2); line-height: 1.55; margin-top: 4px; }