:root {
  color-scheme: light;
  --ink: #20262b;
  --muted: #5c6870;
  --accent: #8b1e2d;
  --line: #d9dee2;
  --soft: #f5f6f7;
  --max: 54rem;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  color: var(--ink);
  background: #fff;
  font-family: Arial, Helvetica, sans-serif;
  font-size: 1rem;
  line-height: 1.6;
}

.wrap {
  width: min(calc(100% - 2rem), var(--max));
  margin-inline: auto;
}

a {
  color: var(--accent);
  text-underline-offset: 0.18em;
}

a:hover { color: #5f111d; }

a:focus-visible,
summary:focus-visible {
  outline: 3px solid #e3aa28;
  outline-offset: 3px;
}

.site-header {
  padding: 3rem 0 2.5rem;
  border-top: 0.4rem solid var(--accent);
  border-bottom: 1px solid var(--line);
}

.kicker {
  margin: 0 0 0.4rem;
  color: var(--accent);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  color: #192d3b;
  font-family: Georgia, "Times New Roman", serif;
  line-height: 1.2;
}

h1 {
  margin: 0;
  font-size: clamp(2.5rem, 7vw, 4.5rem);
  font-weight: 500;
  letter-spacing: -0.035em;
}

.organizers { margin: 0.8rem 0; }

.meeting {
  width: fit-content;
  margin: 1.5rem 0 0;
  padding: 0.8rem 1rem;
  background: var(--soft);
  border-left: 3px solid var(--accent);
}

.year-nav {
  display: flex;
  gap: 1.2rem;
  padding-block: 1rem;
  border-bottom: 1px solid var(--line);
  font-weight: 700;
}

.year-group {
  padding: 2.5rem 0 0;
  scroll-margin-top: 1rem;
}

.year-group + .year-group { padding-top: 4rem; }

.year-heading {
  display: flex;
  align-items: baseline;
  gap: 1rem;
  padding-bottom: 0.7rem;
  border-bottom: 2px solid #192d3b;
}

.year-heading h3 {
  margin: 0;
  font-size: 2rem;
}

.talk-list { display: grid; }

.talk-card {
  display: grid;
  grid-template-columns: 4.5rem minmax(0, 1fr);
  gap: 1.5rem;
  padding: 1.75rem 0;
  border-bottom: 1px solid var(--line);
}

.featured {
  margin-top: 0.5rem;
  padding-inline: 1rem;
  background: #fbf7f7;
  border-left: 3px solid var(--accent);
}

.date-block {
  color: var(--muted);
  line-height: 1.1;
  text-align: center;
}

.date-block span {
  display: block;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.08em;
}

.date-block strong {
  display: block;
  margin: 0.1rem 0;
  color: #192d3b;
  font-family: Georgia, "Times New Roman", serif;
  font-size: 2rem;
  font-weight: 500;
}

.next-label,
.series-label {
  display: inline-block;
  margin-bottom: 0.45rem;
  color: var(--accent);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.07em;
  text-transform: uppercase;
}

.talk-time {
  margin: 0 0 0.35rem;
  color: var(--muted);
  font-size: 0.9rem;
  font-weight: 700;
}

.talk-content h3 {
  margin: 0;
  font-size: clamp(1.35rem, 4vw, 1.85rem);
  font-weight: 500;
}

.speaker {
  margin: 0.5rem 0 1rem;
  color: var(--muted);
}

.talk-note {
  margin: 0.8rem 0;
  padding: 0.6rem 0.8rem;
  background: #fff6d7;
  border-left: 3px solid #d5a32b;
}

details {
  padding-top: 0.75rem;
  border-top: 1px solid var(--line);
}

summary {
  width: fit-content;
  cursor: pointer;
  color: var(--accent);
  font-weight: 700;
}

.abstract {
  max-width: 48rem;
  color: #354149;
}

.abstract p { margin: 0.8rem 0 0; }

.math {
  font-family: Georgia, "Times New Roman", serif;
  font-style: italic;
}

.talk-actions { margin-top: 0.8rem; }

.talk-actions a { font-weight: 700; }

footer {
  margin-top: 4rem;
  padding: 2rem 0;
  color: var(--muted);
  background: var(--soft);
  border-top: 1px solid var(--line);
  font-size: 0.9rem;
}

footer .wrap {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
}

footer p { margin: 0; }

@media (max-width: 38rem) {
  .site-header { padding-top: 2rem; }

  .talk-card {
    grid-template-columns: 1fr;
    gap: 0.8rem;
  }

  .date-block {
    display: flex;
    align-items: baseline;
    gap: 0.35rem;
    text-align: left;
  }

  .date-block strong {
    order: -1;
    font-size: 1.4rem;
  }

  footer .wrap { display: block; }
  footer a { display: inline-block; margin-top: 0.6rem; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}