:root {
  --bg: #fbfaf7;
  --fg: #1f2328;
  --muted: #5d6470;
  --accent: #1d5c8f;
  --rule: #e3e0d8;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #15171a;
    --fg: #e6e6e3;
    --muted: #9aa1ab;
    --accent: #7db4e6;
    --rule: #2c3036;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 17px/1.6 Charter, "Bitstream Charter", "Sitka Text", Cambria, Georgia, serif;
}
main {
  max-width: 56rem;
  margin: 0 auto;
  padding: 4rem 1rem 3rem;
}
h1 { font-size: 2rem; line-height: 1.2; margin: 0 0 0.25rem; letter-spacing: -0.01em; }
h2 { font-size: 1.15rem; margin: 2rem 0 0.5rem; }
p, li { margin: 0 0 0.9rem; }
p, ul, h2, .note { max-width: 40rem; }
ul { padding-left: 1.25rem; }
a { color: var(--accent); text-underline-offset: 2px; }
.lede { color: var(--muted); margin-bottom: 2rem; }
.meta { color: var(--muted); font-size: 0.9rem; }
nav {
  font: 0.9rem/1.4 -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  margin-bottom: 2.5rem;
}
nav a { margin-right: 1rem; text-decoration: none; }
nav a[aria-current="page"] { color: var(--fg); font-weight: 600; }
footer {
  border-top: 1px solid var(--rule);
  margin-top: 3rem;
  padding-top: 1rem;
  color: var(--muted);
  font-size: 0.85rem;
}
.videos {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 24rem), 1fr));
  gap: 1.5rem;
  margin: 1.5rem 0 2rem;
}
figure { margin: 0; }
.frame {
  position: relative;
  aspect-ratio: 16 / 9;
  background: var(--rule);
  border-radius: 6px;
  overflow: hidden;
}
.frame iframe { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; }
figcaption { margin-top: 0.5rem; font-size: 0.95rem; }
figcaption span { color: var(--muted); }
.note {
  border-left: 3px solid var(--accent);
  padding: 0.25rem 0 0.25rem 1rem;
  margin: 2rem 0;
}