/* ==========================================================
   Tina Khezresmaeilzadeh — site stylesheet
   Colors live in the token blocks below; edit them there.
   ========================================================== */
:root {
  --bg: #F6F7F9;
  --surface: #FFFFFF;
  --ink: #18202E;
  --muted: #5A6476;
  --line: #DDE2EA;
  --accent: #2B5C8A;
  --accent-soft: #E7EEF6;
  --tag-bg: #EEF1F5;
  --shadow: 0 1px 2px rgba(24,32,46,.05), 0 6px 18px rgba(24,32,46,.06);
  --serif: "Newsreader", Georgia, "Times New Roman", serif;
  --sans: "Public Sans", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  --maxw: 980px;
  color-scheme: light;
}
:root[data-theme="dark"] {
  --bg: #0E1525;
  --surface: #151E31;
  --ink: #E4E9F1;
  --muted: #98A3B6;
  --line: #26314A;
  --accent: #8DB8E8;
  --accent-soft: #1B2A45;
  --tag-bg: #1C2639;
  --shadow: 0 1px 2px rgba(0,0,0,.3), 0 8px 24px rgba(0,0,0,.25);
  color-scheme: dark;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } * { transition: none !important; } }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16.5px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  transition: background-color .25s ease, color .25s ease;
  min-height: 100vh; display: flex; flex-direction: column;
}
main { flex: 1; }
img { max-width: 100%; display: block; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 4px; }

.skip { position: absolute; left: -999px; top: 8px; background: var(--surface); padding: 8px 12px; z-index: 100; }
.skip:focus { left: 8px; }

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ---------- Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: saturate(160%) blur(10px);
  -webkit-backdrop-filter: saturate(160%) blur(10px);
  border-bottom: 1px solid var(--line);
}
.site-header .wrap { display: flex; align-items: center; gap: 20px; height: 62px; }
.brand { font-family: var(--serif); font-size: 1.2rem; font-weight: 500; color: var(--ink); white-space: nowrap; }
.brand:hover { text-decoration: none; color: var(--accent); }
.nav { display: flex; gap: 4px; margin-left: auto; overflow-x: auto; scrollbar-width: none; }
.nav::-webkit-scrollbar { display: none; }
.nav a { color: var(--muted); font-size: .95rem; padding: 6px 12px; border-radius: 8px; white-space: nowrap; }
.nav a:hover { color: var(--ink); background: var(--tag-bg); text-decoration: none; }
.nav a[aria-current="page"] { color: var(--ink); font-weight: 600; }

.theme-toggle {
  flex: none; width: 38px; height: 38px; border-radius: 50%;
  display: grid; place-items: center;
  border: 1px solid var(--line); background: var(--surface); color: var(--ink);
  cursor: pointer;
}
.theme-toggle:hover { border-color: var(--accent); color: var(--accent); }
.theme-toggle svg { width: 18px; height: 18px; }
.theme-toggle .sun { display: none; }
:root[data-theme="dark"] .theme-toggle .sun { display: block; }
:root[data-theme="dark"] .theme-toggle .moon { display: none; }

/* ---------- Page scaffolding ---------- */
main { padding: 56px 0 80px; }
.page-head { margin-bottom: 40px; max-width: 68ch; }
.page-head h1 { font-family: var(--serif); font-weight: 500; font-size: clamp(2.1rem, 4vw, 2.8rem); line-height: 1.15; margin: 0 0 12px; letter-spacing: -.01em; }
.page-head p { color: var(--muted); margin: 0; font-size: 1.05rem; }

section + section { margin-top: 64px; }
h2.section-title {
  font-family: var(--serif); font-weight: 500; font-size: 1.65rem;
  margin: 0 0 24px; padding-bottom: 10px; border-bottom: 1px solid var(--line);
}
h3 { font-family: var(--serif); font-weight: 500; }

/* ---------- Home: profile ---------- */
.profile { display: grid; grid-template-columns: 250px 1fr; gap: 48px; align-items: start; }
.profile-card { position: sticky; top: 90px; }
.profile-photo { width: 100%; aspect-ratio: 4/5; object-fit: cover; border-radius: 14px; background: var(--tag-bg); }
.profile-card h1 { font-family: var(--serif); font-weight: 500; font-size: 1.75rem; line-height: 1.2; margin: 20px 0 4px; }
.profile-card .role { color: var(--muted); font-size: .95rem; margin: 0; line-height: 1.5; }
.links { list-style: none; padding: 0; margin: 18px 0 0; display: grid; gap: 6px; }
.links a { display: inline-flex; align-items: center; gap: 10px; color: var(--ink); font-size: .95rem; }
.links a:hover { color: var(--accent); }
.links svg { width: 17px; height: 17px; color: var(--muted); flex: none; }

.bio:empty, .bio:not(:has(p)) { display: none; }
.bio + section { margin-top: 0; }
.bio p { margin: 0 0 1.1em; max-width: 68ch; }
.bio p:first-child { font-family: var(--serif); font-size: 1.2rem; line-height: 1.5; color: var(--ink); }

/* ---------- Timeline (experience / education) ---------- */
.timeline { list-style: none; margin: 0; padding: 0; }
.timeline li { display: grid; grid-template-columns: 130px 40px 1fr; gap: 18px; align-items: start; padding: 16px 0; border-bottom: 1px solid var(--line); }
.timeline .logo { width: 40px; height: 40px; border-radius: 9px; border: 1px solid var(--line); background: #fff; object-fit: contain; }
.timeline li:last-child { border-bottom: 0; }
.timeline .when { color: var(--muted); font-size: .9rem; font-variant-numeric: tabular-nums; padding-top: 2px; }
.timeline .org { font-weight: 600; margin: 0; }
.timeline .what { color: var(--muted); margin: 2px 0 0; font-size: .95rem; }

/* ---------- Publications ---------- */
.pub-year { font-family: var(--serif); font-size: 1.25rem; color: var(--muted); margin: 36px 0 8px; font-weight: 500; }
.pub-year:first-of-type { margin-top: 0; }
.pubs { list-style: none; margin: 0; padding: 0; }
.pub { padding: 16px 0; border-bottom: 1px solid var(--line); }
.pub:last-child { border-bottom: 0; }
.pub-title { font-weight: 600; margin: 0; line-height: 1.45; }
.pub-title a { color: var(--ink); }
.pub-title a:hover { color: var(--accent); }
.pub-authors { margin: 4px 0 0; font-size: .93rem; color: var(--muted); }
.pub-authors .me { color: var(--ink); font-weight: 600; }
.pub-venue { margin: 4px 0 0; font-size: .93rem; color: var(--muted); font-style: italic; }
.badge { display: inline-block; font-style: normal; font-size: .75rem; font-weight: 600; padding: 1px 8px; border-radius: 999px; background: var(--accent-soft); color: var(--accent); margin-left: 6px; vertical-align: 1px; }
.pub-links { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 10px; }

.btn {
  display: inline-flex; align-items: center; gap: 6px;
  font-size: .85rem; font-weight: 500; padding: 4px 12px;
  border: 1px solid var(--line); border-radius: 999px; color: var(--ink); background: var(--surface);
}
.btn:hover { border-color: var(--accent); color: var(--accent); text-decoration: none; }
.btn.primary { background: var(--accent); border-color: var(--accent); color: var(--bg); }
.btn.primary:hover { color: var(--bg); opacity: .9; }
.more { margin-top: 24px; display: inline-block; font-weight: 500; }

/* ---------- Research directions ---------- */
.directions { display: grid; gap: 20px; }
.direction { background: var(--surface); border: 1px solid var(--line); border-radius: 14px; padding: 28px 30px; }
.direction h2 { font-family: var(--serif); font-weight: 500; font-size: 1.5rem; margin: 0 0 10px; }
.direction .desc { margin: 0 0 16px; max-width: 70ch; min-height: 1em; }
.direction .desc:empty { display: none; }
.tags { display: flex; flex-wrap: wrap; gap: 8px; margin: 0; padding: 0; list-style: none; }
.tags li { font-size: .82rem; padding: 3px 11px; border-radius: 999px; background: var(--tag-bg); color: var(--muted); }
.related { margin: 18px 0 0; padding-top: 16px; border-top: 1px dashed var(--line); font-size: .93rem; }
.related span { color: var(--muted); margin-right: 6px; }
.related a { margin-right: 14px; }
.jump { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 20px; }

/* ---------- Project cards ---------- */
.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 22px; }
.card {
  position: relative; display: flex; flex-direction: column;
  background: var(--surface); border: 1px solid var(--line); border-radius: 14px; overflow: hidden;
  color: var(--ink); transition: border-color .2s ease, transform .2s ease;
}
.card:hover { border-color: var(--accent); transform: translateY(-2px); text-decoration: none; }
.card-thumb { aspect-ratio: 1/1; background: var(--accent-soft); display: grid; place-items: center; overflow: hidden; }
.card-thumb img { width: 100%; height: 100%; object-fit: cover; }
.card-thumb .mark { font-family: var(--serif); font-size: 2.4rem; color: var(--accent); letter-spacing: .02em; }
.card-body { padding: 18px 20px 20px; display: flex; flex-direction: column; gap: 8px; flex: 1; }
.card-body h3 { margin: 0; font-size: 1.2rem; line-height: 1.3; }
.card-venue { margin: 0; font-size: .88rem; color: var(--muted); }
.card-blurb { margin: 0; font-size: .95rem; }
.card-blurb:empty { display: none; }
.card .tags { margin-top: auto; padding-top: 6px; }
/* Whole card is clickable via the title link; the buttons sit above it */
.card-body h3 a { color: inherit; }
.card-body h3 a::after { content: ""; position: absolute; inset: 0; border-radius: inherit; }
.card-body h3 a:hover { text-decoration: none; }
.card:focus-within { border-color: var(--accent); }
.card-links { position: relative; z-index: 1; display: flex; flex-wrap: wrap; gap: 8px; padding-top: 4px; }
.btn svg { width: 14px; height: 14px; flex: none; }
.resources { margin: 0; padding-left: 1.2em; }
.resources li + li { margin-top: 8px; }

/* ---------- Project (paper) page ---------- */
.paper-head { text-align: center; max-width: 820px; margin: 0 auto 36px; }
.paper-head .venue { color: var(--accent); font-weight: 600; font-size: .95rem; margin: 0 0 12px; }
.paper-head h1 { font-family: var(--serif); font-weight: 500; font-size: clamp(1.9rem, 4vw, 2.6rem); line-height: 1.2; margin: 0 0 16px; }
.paper-head .authors { margin: 0; font-size: 1.02rem; }
.paper-head .affil { margin: 6px 0 0; color: var(--muted); font-size: .93rem; }
.paper-head .pub-links { justify-content: center; margin-top: 22px; }
.paper-head .btn { font-size: .92rem; padding: 7px 16px; }
.figure { margin: 0 auto 40px; max-width: 900px; }
.figure-slot {
  aspect-ratio: 16/7; border: 1px dashed var(--line); border-radius: 14px;
  display: grid; place-items: center; color: var(--muted); font-size: .9rem; background: var(--surface);
}
.figure img { border-radius: 12px; border: 1px solid var(--line); }
.figure figcaption { color: var(--muted); font-size: .9rem; margin-top: 10px; text-align: center; }
.paper-body { max-width: 760px; margin: 0 auto; }
.paper-body section + section { margin-top: 44px; }
.paper-body h2 { font-family: var(--serif); font-weight: 500; font-size: 1.5rem; margin: 0 0 12px; }
.paper-body p { margin: 0 0 1em; }
.placeholder { color: var(--muted); font-style: italic; }
.bibtex { position: relative; }
.bibtex pre {
  margin: 0; padding: 18px 20px; background: var(--surface); border: 1px solid var(--line); border-radius: 12px;
  font-family: var(--mono); font-size: .82rem; line-height: 1.6; overflow-x: auto; color: var(--ink);
}
.copy-btn { position: absolute; top: 10px; right: 10px; cursor: pointer; font-family: var(--sans); }
.back { display: inline-block; margin-bottom: 28px; font-size: .95rem; }

/* ---------- Footer ---------- */
.site-footer { border-top: 1px solid var(--line); padding: 28px 0 40px; color: var(--muted); font-size: .88rem; }
.site-footer .wrap { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px; }
.site-footer a { color: var(--muted); }
.site-footer a:hover { color: var(--accent); }
.site-footer nav { display: flex; gap: 18px; }

/* ---------- Responsive ---------- */
@media (max-width: 760px) {
  body { font-size: 16px; }
  .site-header .wrap { gap: 10px; }
  .brand { font-size: 1.05rem; }
  .nav a { padding: 6px 8px; font-size: .9rem; }
  main { padding-top: 36px; }
  .profile { grid-template-columns: 1fr; gap: 28px; }
  .profile-card { position: static; display: grid; grid-template-columns: 120px 1fr; gap: 0 20px; align-items: center; }
  .profile-photo { grid-row: span 2; aspect-ratio: 1; border-radius: 50%; }
  .profile-card h1 { margin-top: 0; font-size: 1.45rem; }
  .profile-card .links { grid-column: 1 / -1; display: flex; flex-wrap: wrap; gap: 8px 18px; }
  .timeline li { grid-template-columns: 40px 1fr; gap: 6px 14px; }
  .timeline .when { grid-column: 1 / -1; }
  .direction { padding: 22px; }
}
@media (max-width: 520px) {
  .brand .full { display: none; }
}
@media (max-width: 440px) {
  .brand { display: none; }
  .nav { margin-left: 0; }
  .theme-toggle { margin-left: auto; }
  .nav { gap: 0; }
  .nav a { padding: 6px 7px; font-size: .86rem; }
}