/* Orange variant: serif headings (Source Serif 4), Inter body text,
   burnt-orange accent, round photo, warm footer. */

:root {
  --accent: #c2410c;        /* burnt orange, 5.2:1 contrast on white */
  --accent-dark: #9a3412;   /* hover */
  --accent-soft: #fff7ed;   /* tinted backgrounds */
  --accent-line: #fdba74;   /* thin orange rules */
  --ink: #1c1917;
  --text: #3f3a36;
  --muted: #78716c;
  --rule: #e7e5e4;
  --bg: #ffffff;
  --bg-warm: #faf7f2;
  --serif: "Source Serif 4", Georgia, serif;
  --sans: Inter, ui-sans-serif, system-ui, sans-serif;
}

* { box-sizing: border-box; }

html, body { margin: 0; overflow-x: clip; }

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  border-top: 4px solid var(--accent);   /* thin orange band across the top */
}

h1, h2, p, ul { margin: 0; padding: 0; }
a { color: inherit; text-decoration: none; }

/* Shared link style: orange, underline appears on hover */
.intro-text a,
.paper-title a,
.paper-authors a,
.paper-note a,
.paper-press a,
.paper-resources a {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-color: transparent;
  text-underline-offset: 3px;
  transition: color 0.15s ease, text-decoration-color 0.15s ease;
}
.intro-text a:hover,
.paper-title a:hover,
.paper-authors a:hover,
.paper-note a:hover,
.paper-press a:hover,
.paper-resources a:hover {
  color: var(--accent-dark);
  text-decoration-color: currentColor;
}

/* ---------- Header ---------- */
.header {
  background: var(--bg);
  border-bottom: 1px solid var(--rule);
}

.nav-container {
  max-width: 880px;
  margin: 0 auto;
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 2rem;
}

.nav-brand {
  font-family: var(--serif);
  font-size: 1.3rem;
  font-weight: 600;
  color: var(--ink);
  white-space: nowrap;
}
.nav-brand:hover { color: var(--accent); }

.nav-menu {
  display: flex;
  list-style: none;
  gap: 1.75rem;
}

.nav-link {
  color: var(--muted);
  font-size: 0.85rem;
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  transition: color 0.15s ease;
}
.nav-link:hover { color: var(--accent); }

/* ---------- Main column ---------- */
.main-content {
  flex: 1;
  width: 100%;
  max-width: 880px;
  margin: 0 auto;
  padding: 2.5rem 2rem 2rem;
}

/* ---------- Hero: round photo + bio ---------- */
.hero {
  display: flex;
  gap: 3rem;
  align-items: flex-start;
  margin-bottom: 3.5rem;
}

/* Full photo in a 3:4 rectangle (same ratio as the picture, so nothing is cropped) */
.avatar {
  flex: 0 0 auto;
  width: 240px;
  aspect-ratio: 3 / 4;
  height: auto;
  border-radius: 8px;
  object-fit: cover;
  box-shadow: 0 2px 10px #0000001a;
  margin-top: 0.4rem;
}

.hero-info { flex: 1; min-width: 0; }

.author-name {
  font-family: var(--serif);
  color: var(--ink);
  font-size: 2.4rem;
  font-weight: 700;
  line-height: 1.1;
  margin-bottom: 0.35rem;
}

.author-info {
  color: var(--accent);
  font-size: 0.9rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: 0.25rem;
}

.author-fields {
  color: var(--muted);
  font-size: 0.92rem;
}
.author-fields:last-of-type { margin-bottom: 1.25rem; }

.intro-text {
  color: var(--text);
  font-size: 1rem;
  line-height: 1.75;
}
.intro-text p + p { margin-top: 0.6rem; }
.intro-text a { font-weight: 500; }
.intro-text strong { color: var(--ink); font-weight: 600; }

/* Email lines under the bio */
.contact {
  margin-top: 1.1rem;
  padding-top: 0.9rem;
  border-top: 1px solid var(--rule);
  color: var(--muted);
  font-size: 0.88rem;
}
.contact a { color: var(--text); }
.contact a:hover { color: var(--accent); }

/* ---------- Research list ---------- */
.research { padding-bottom: 2rem; }

.research-section { margin-bottom: 2.5rem; }

/* Serif heading with a short orange bar in front */
.research-section h2 {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-family: var(--serif);
  color: var(--ink);
  font-size: 1.45rem;
  font-weight: 600;
  margin-bottom: 1.1rem;
}
.research-section h2::before {
  content: "";
  width: 28px;
  height: 3px;
  background: var(--accent);
  border-radius: 2px;
}

.paper-list { list-style: none; }

.paper {
  margin-bottom: 1.5rem;
  padding-left: 1rem;
  border-left: 2px solid var(--rule);
}

.paper-title {
  font-family: var(--serif);
  color: var(--ink);
  font-size: 1.12rem;
  font-weight: 600;
  line-height: 1.35;
}

.paper-authors {
  margin-top: 0.2rem;
  color: var(--text);
  font-size: 0.92rem;
}

.paper-desc {
  margin-top: 0.2rem;
  color: var(--muted);
  font-size: 0.9rem;
}

/* Award / presentation line */
.paper-note {
  margin-top: 0.2rem;
  color: var(--muted);
  font-size: 0.88rem;
}

/* [arXiv] [PDF] as small outlined pills */
.paper-resources {
  margin-top: 0.5rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}
.paper-resources a {
  padding: 0.1rem 0.55rem;
  border: 1px solid var(--accent-line);
  border-radius: 999px;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.02em;
}
.paper-resources a:hover {
  background: var(--accent-soft);
  text-decoration-color: transparent;
}

.paper-press {
  margin-top: 0.4rem;
  color: var(--muted);
  font-size: 0.86rem;
}

/* "+ Abstract" toggle, built on <details> */
.paper-abstract { margin-top: 0.35rem; }
.paper-abstract summary {
  list-style: none;
  cursor: pointer;
  color: var(--accent);
  font-size: 0.86rem;
  font-weight: 600;
}
.paper-abstract summary::-webkit-details-marker { display: none; }
.paper-abstract summary::before { content: "+ "; }
.paper-abstract[open] summary::before { content: "\2212  "; }
.paper-abstract summary:hover { color: var(--accent-dark); }
.paper-abstract p {
  margin-top: 0.5rem;
  padding: 0.8rem 1rem;
  color: var(--text);
  font-size: 0.9rem;
  line-height: 1.7;
  background: var(--accent-soft);
  border-radius: 6px;
}

/* ---------- Footer ---------- */
.footer {
  background: var(--bg-warm);
  border-top: 1px solid var(--rule);
  padding: 2.25rem 2rem;
  margin-top: 3rem;
}

/* Email left, icons centre, address right */
.footer-grid {
  max-width: 880px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 1.5rem;
}

.footer-email {
  color: var(--text);
  font-size: 0.9rem;
  font-weight: 600;
}
.footer-email:hover { color: var(--accent); }

.social-links { display: flex; justify-content: center; gap: 1.5rem; }
.social-links a {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  color: var(--muted);
  transition: color 0.15s ease;
}
.social-links a:hover { color: var(--accent); }
.social-links svg { width: 20px; height: 20px; }
.social-links svg.icon-pse { width: 24px; height: 24px; } /* round logo needs a bit more size to match the square */

.footer-address {
  color: var(--muted);
  font-size: 0.88rem;
  font-style: normal;
  text-align: right;
}

.footer-divider {
  width: 40px;
  height: 2px;
  margin: 1.5rem auto 1rem;
  background: var(--accent-line);
}

.footer-bottom {
  text-align: center;
  color: #a8a29e;
  font-size: 0.82rem;
}

/* ---------- Phone and tablet ---------- */
@media (max-width: 768px) {
  .nav-container { padding: 0.85rem 1rem; }
  .main-content { padding: 1.5rem 1rem 1rem; }

  .hero {
    flex-direction: column;
    align-items: center;
    gap: 1.25rem;
    margin-bottom: 2.5rem;
  }
  .hero-info { width: 100%; }
  .author-name, .author-info, .author-fields { text-align: center; }
  .avatar { width: 200px; margin-top: 0; }
  .intro-text { font-size: 0.97rem; }

  .footer { padding: 2rem 1rem; margin-top: 2rem; }
  .footer-grid { grid-template-columns: 1fr; text-align: center; gap: 1rem; }
  .footer-address { text-align: center; }
}

@media (max-width: 480px) {
  .author-name { font-size: 1.9rem; }
  .nav-menu { gap: 1.25rem; }
}