/* Project page styling, following the academic-page conventions of
   agenticlearning.ai: Libertinus Sans for structure, Libertinus Serif for
   prose, a single 896px column, and generous vertical rhythm. */

:root {
  --fg: #1f2328;
  --fg-muted: #6b7280;
  --bg: #ffffff;
  --band-bg: #f6f7f8;
  --rule: #e3e6e9;
  --link: #2b5fa8;
  --sans: "Libertinus Sans", "Segoe UI", system-ui, sans-serif;
  --serif: "Libertinus Serif", Georgia, "Times New Roman", serif;
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--sans);
  line-height: 1.6;
}

.wrap { max-width: 896px; margin: 0 auto; padding: 0 1.5rem; }

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

/* ---------- hero ---------- */
.hero { text-align: center; padding: 4.5rem 1.5rem 2rem; }
.hero h1 {
  font-size: 2.6rem;
  line-height: 1.18;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin: 0 0 0.6rem;
}
.subtitle {
  font-size: 1.28rem;
  color: var(--fg-muted);
  margin: 0 0 1.6rem;
  font-weight: 400;
}
.authors { font-size: 1.08rem; margin: 0 0 0.35rem; }
.authors sup, .affil sup { font-size: 0.72em; }
.affil { font-size: 0.98rem; color: var(--fg-muted); margin: 0 0 1.8rem; }

.buttons { display: flex; gap: 0.7rem; justify-content: center; flex-wrap: wrap; }
.btn {
  display: inline-block;
  padding: 0.5rem 1.15rem;
  border: 1px solid var(--fg);
  border-radius: 999px;
  color: var(--fg);
  font-size: 0.98rem;
  transition: background 0.15s ease, color 0.15s ease;
}
.btn:hover { background: var(--fg); color: #fff; text-decoration: none; }

/* ---------- prose ---------- */
.prose, .prose-body p, .prose-body li {
  font-family: var(--serif);
  font-size: 1.12rem;
  line-height: 1.72;
}
.tldr { padding: 0 1.5rem 2.5rem; }
.tldr .prose { margin: 0; }
.sc { font-variant: small-caps; }

.band { background: var(--band-bg); padding: 3.5rem 0; }
.band h2 { margin-top: 0; }
.centered { text-align: center; }

/* ---------- contents ---------- */
.toc {
  padding-top: 2rem;
  padding-bottom: 2.5rem;
  font-size: 0.98rem;
  border-bottom: 1px solid var(--rule);
}
.toc-label { color: var(--fg-muted); margin-right: 0.6rem; }
.toc a { margin-right: 1.1rem; }

/* ---------- sections ---------- */
.section { padding: 3rem 1.5rem; border-bottom: 1px solid var(--rule); }
.section:last-child { border-bottom: none; }
h2 {
  font-size: 1.9rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin: 0 0 1.2rem;
}

/* ---------- figures ---------- */
figure { margin: 2.4rem 0; text-align: center; }
figure img, figure video {
  width: 100%;
  height: auto;
  border-radius: 4px;
  display: block;
}
figcaption {
  font-family: var(--serif);
  font-style: italic;
  font-size: 1rem;
  color: var(--fg-muted);
  margin-top: 0.75rem;
  text-align: left;
  line-height: 1.55;
}
figure.wide { margin: 2.4rem 0 2.8rem; }

/* ---------- video rows ---------- */
.video-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
  margin: 2.2rem 0;
}
.video-row.half { grid-template-columns: repeat(2, 1fr); max-width: 620px; margin-inline: auto; }
.video-row figure { margin: 0; }
.video-row video { border: 1px solid var(--rule); }
.video-row figcaption {
  font-size: 0.92rem;
  text-align: center;
  margin-top: 0.5rem;
}

/* ---------- takeaways ---------- */
.takeaways { padding-left: 1.3rem; }
.takeaways li { margin-bottom: 0.55rem; }

/* ---------- bibtex ---------- */
.bibtex {
  background: var(--band-bg);
  border: 1px solid var(--rule);
  border-radius: 6px;
  padding: 1.1rem 1.25rem;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.86rem;
  line-height: 1.55;
  overflow-x: auto;
}

/* ---------- footer ---------- */
.site-footer {
  border-top: 1px solid var(--rule);
  padding: 2.5rem 0 3.5rem;
  font-size: 0.95rem;
}
.site-footer p { margin: 0.3rem 0; }
.muted { color: var(--fg-muted); }

/* ---------- responsive ---------- */
@media (max-width: 760px) {
  .hero h1 { font-size: 1.95rem; }
  .subtitle { font-size: 1.08rem; }
  .video-row { grid-template-columns: repeat(2, 1fr); }
  .section { padding: 2.2rem 1.25rem; }
  .prose, .prose-body p, .prose-body li { font-size: 1.05rem; }
}
@media (max-width: 460px) {
  .video-row, .video-row.half { grid-template-columns: 1fr; }
}