:root {
  --bg: #fdfdfc;
  --fg: #1c1e21;
  --muted: #5a6069;
  --accent: #0f62a8;
  --accent-soft: #e3eef7;
  --rule: #e2e2df;
  --hero-bg: #10314e;
  --hero-fg: #f2f6fa;
  --hero-muted: #b8c9da;
  --tag-bg: #eef1f4;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #15171a;
    --fg: #e6e8ea;
    --muted: #9aa3ad;
    --accent: #6db3e8;
    --accent-soft: #1d3448;
    --rule: #2a2e33;
    --hero-bg: #0c2036;
    --hero-fg: #f2f6fa;
    --hero-muted: #93a9bd;
    --tag-bg: #23272c;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
               "Helvetica Neue", Arial, sans-serif;
  font-size: 1.05rem;
  line-height: 1.65;
  color: var(--fg);
  background: var(--bg);
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ---------- hero ---------- */

.hero {
  background: var(--hero-bg);
  color: var(--hero-fg);
  padding: 3.5rem 1.5rem;
}

.hero-inner {
  max-width: 46rem;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 2rem;
  flex-wrap: wrap;
}

.avatar {
  width: 8rem;
  height: 8rem;
  border-radius: 50%;
  object-fit: cover;
  border: 3px solid rgba(255, 255, 255, 0.25);
  flex-shrink: 0;
}

.hero h1 {
  margin: 0 0 0.3rem;
  font-size: 2.1rem;
  line-height: 1.2;
}

.tagline {
  margin: 0 0 0.2rem;
  font-weight: 500;
  font-size: 1.25rem;
  min-height: 1.65em;
}

.dirac {
  font-family: "STIX Two Math", "Cambria Math", Georgia, "Times New Roman", serif;
  font-size: 1.15rem;
  letter-spacing: 0.01em;
}

#superposition {
  transition: opacity 0.45s ease;
  color: #8ecdf7;
  text-shadow: 0 0 14px rgba(142, 205, 247, 0.45);
}

.affiliation {
  margin: 0 0 0.9rem;
  color: var(--hero-muted);
  font-size: 0.95rem;
}

.contact-links {
  display: flex;
  gap: 0.6rem;
  flex-wrap: wrap;
}

.contact-links a {
  color: var(--hero-fg);
  border: 1px solid rgba(255, 255, 255, 0.35);
  border-radius: 999px;
  padding: 0.25rem 0.9rem;
  font-size: 0.9rem;
}

.contact-links a:hover {
  background: rgba(255, 255, 255, 0.12);
  text-decoration: none;
}

/* ---------- main ---------- */

main {
  max-width: 46rem;
  margin: 0 auto;
  padding: 1rem 1.5rem 3rem;
}

section {
  padding: 1.8rem 0;
  border-bottom: 1px solid var(--rule);
}

section:last-of-type { border-bottom: none; }

h2 {
  font-size: 1.35rem;
  margin: 0 0 0.8rem;
}

h3 {
  font-size: 1.02rem;
  margin: 1.4rem 0 0.5rem;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

p { margin: 0 0 0.8rem; }

/* topics + tags */

.topics { padding-left: 1.2rem; margin: 0; }
.topics li { margin-bottom: 0.3rem; }

.tags {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.tags li {
  background: var(--tag-bg);
  border-radius: 999px;
  padding: 0.2rem 0.85rem;
  font-size: 0.9rem;
}

/* publications */

.pub-list { padding-left: 1.2rem; margin: 0; }
.pub-list li { margin-bottom: 1.1rem; }
.pub-title { font-weight: 600; }
.pub-authors { font-size: 0.95rem; }
.pub-venue { color: var(--muted); font-size: 0.9rem; font-style: italic; }

/* timeline */

.timeline {
  display: grid;
  grid-template-columns: 8.5rem 1fr;
  row-gap: 0.9rem;
  margin: 0;
}

.timeline dt {
  color: var(--muted);
  font-size: 0.92rem;
  padding-top: 0.1rem;
}

.timeline dd { margin: 0; }

/* contact */

.contact-list { list-style: none; padding: 0; margin: 0; }
.contact-list li { margin-bottom: 0.4rem; }

/* footer */

footer {
  border-top: 1px solid var(--rule);
  padding: 1.2rem 1.5rem 2rem;
  text-align: center;
  color: var(--muted);
  font-size: 0.85rem;
}

/* ---------- small screens ---------- */

@media (max-width: 540px) {
  .hero { padding: 2.5rem 1.2rem; }
  .hero-inner { gap: 1.2rem; }
  .avatar { width: 5.2rem; height: 5.2rem; font-size: 1.8rem; }
  .hero h1 { font-size: 1.7rem; }
  .dirac { font-size: 0.95rem; }
  .timeline { grid-template-columns: 1fr; row-gap: 0.2rem; }
  .timeline dd { margin-bottom: 0.8rem; }
}