:root { color-scheme: light; }
* { box-sizing: border-box; }
body {
  margin: 0; padding: 2.5rem 1rem 4rem;
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
  line-height: 1.65; color: #1f2937; background: #f9fafb;
}
main { max-width: 46rem; margin: 0 auto; background: #fff;
  border: 1px solid #e5e7eb; border-radius: 1rem; padding: 2rem 1.75rem; }
h1 { font-size: 1.6rem; margin: 0 0 1.5rem; }
h2 { font-size: 1.1rem; margin: 2rem 0 .5rem; }
p, li { font-size: .95rem; }
dl { margin: .5rem 0 1.25rem; }
dt { font-weight: 600; margin-top: .75rem; font-size: .9rem; }
dd { margin: 0; }
a { color: #1f2937; }
.todo { display: inline-block; background: #fef3c7; border: 1px solid #fcd34d;
  border-radius: .35rem; padding: .05rem .4rem; font-size: .85rem; color: #92400e; }
.note { margin-top: 2.5rem; padding: 1rem; background: #f3f4f6;
  border-radius: .5rem; font-size: .82rem; color: #6b7280; }
footer { max-width: 46rem; margin: 1.5rem auto 0; font-size: .8rem; color: #6b7280; text-align: center; }