:root {
  --bg: #ffffff; --fg: #1f1b24; --muted: #6b6475; --line: #e6e1ee; --purple: #8b20e8; --purple-dark: #690fc5; --gold: #ffc51b; --mark: #fff3bf;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #15121a; --fg: #ece8f2; --muted: #a59db3; --line: #2e2838; --mark: #5a4a00; }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; min-height: 100vh; display: flex; flex-direction: column;
  background: var(--bg); color: var(--fg);
  font: 16px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}
a { color: var(--purple); }
@media (prefers-color-scheme: dark) { a { color: #c28cff; } }
main { flex: 1; width: 100%; max-width: 760px; margin: 0 auto; padding: 32px 20px; }
main.center { display: flex; flex-direction: column; align-items: center; justify-content: center; text-align: center; gap: 28px; }
.logo { width: min(440px, 88vw); height: auto; display: block; }
.button {
  display: inline-block; padding: 14px 28px; border-radius: 999px; background: var(--purple); color: #fff; text-decoration: none;
  font-weight: 700; font-size: 1.05rem;
}
.button:hover, .button:focus-visible { background: var(--purple-dark); }
footer { padding: 20px; text-align: center; color: var(--muted); font-size: .9rem; border-top: 1px solid var(--line); }
footer a { color: inherit; margin: 0 10px; }
footer p { margin: 8px auto 0; max-width: none; font-size: .8rem; }
h1 { font-size: 1.9rem; line-height: 1.25; margin: 0 0 .3em; }
h2 { font-size: 1.25rem; margin: 2em 0 .4em; padding-top: .4em; border-top: 1px solid var(--line); }
h3 { font-size: 1.05rem; margin: 1.4em 0 .2em; }
p, li { max-width: 68ch; }
.back { display: inline-block; margin-bottom: 1.2em; font-size: .95rem; }
.meta { color: var(--muted); font-size: .9rem; }
mark { background: var(--mark); color: inherit; padding: 0 .2em; border-radius: 3px; }
nav.toc ol { columns: 2; column-gap: 2em; padding-left: 1.2em; }
@media (max-width: 560px) { nav.toc ol { columns: 1; } }