:root { --ink: #1c2430; --muted: #5d6b7a; --line: #e2e6ea; --bg: #fbfcfd; }
* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--ink);
  font: 16px/1.65 -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; }
.wrap { max-width: 44rem; margin: 0 auto; padding: 3rem 1.25rem 4rem; }
header { border-bottom: 1px solid var(--line); padding-bottom: 1.25rem; margin-bottom: 2rem; }
h1 { font-size: 1.5rem; margin: 0 0 .35rem; letter-spacing: -.01em; }
h2 { font-size: 1.1rem; margin: 2rem 0 .5rem; }
.sub { color: var(--muted); margin: 0; font-size: .95rem; }
nav a { color: var(--muted); text-decoration: none; margin-right: 1.1rem; font-size: .9rem; }
nav a:hover { color: var(--ink); }
ul { padding-left: 1.1rem; }
li { margin: .35rem 0; }
footer { margin-top: 3rem; padding-top: 1.25rem; border-top: 1px solid var(--line);
  color: var(--muted); font-size: .85rem; }