:root {
  --bg: #fafafa;
  --fg: #1a1a1a;
  --muted: #666;
  --line: #ddd;
  --code-bg: #f0f0f0;
  --link: #0b5cad;
  color-scheme: light dark;
}

/* Dark palette: follows the OS unless the switch pinned a theme (data-theme on <html>). */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #111;
    --fg: #e6e6e6;
    --muted: #999;
    --line: #333;
    --code-bg: #1c1c1c;
    --link: #7ab7ff;
  }
}

:root[data-theme="dark"] {
  --bg: #111;
  --fg: #e6e6e6;
  --muted: #999;
  --line: #333;
  --code-bg: #1c1c1c;
  --link: #7ab7ff;
  color-scheme: dark;
}

:root[data-theme="light"] { color-scheme: light; }

[hidden] { display: none !important; }

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

main {
  max-width: 42rem;
  margin: 0 auto;
  padding: 3rem 1.25rem;
}

h1 { font-size: 1.75rem; margin: 0 0 2rem; }

h2 {
  font-size: .8rem;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 2.5rem 0 .75rem;
}

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

/* Theme switch */
.topbar { display: flex; justify-content: flex-end; margin: -1.5rem 0 1.5rem; }
.theme-toggle {
  padding: .25rem .7rem;
  background: transparent;
  color: var(--fg);
  border: 1px solid var(--line);
  border-radius: 6px;
  font-family: inherit;
  font-size: .85rem;
  line-height: 1.4;
  cursor: pointer;
}
.theme-toggle:hover { border-color: var(--muted); }
.theme-toggle:focus-visible { outline: 2px solid var(--link); outline-offset: 2px; }

/* Contact list */
dl {
  display: grid;
  grid-template-columns: max-content 1fr;
  gap: .5rem 1.5rem;
  margin: 0;
}
dt { color: var(--muted); }
dd { margin: 0; overflow-wrap: anywhere; }

/* Key blocks */
.key { margin: 0 0 1.25rem; }
.key p { margin: 0 0 .35rem; color: var(--muted); font-size: .9rem; }

pre {
  margin: 0;
  padding: .75rem 1rem;
  background: var(--code-bg);
  border: 1px solid var(--line);
  border-radius: 6px;
  overflow-x: auto;
  font: .85rem/1.5 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

/* Error pages (403/404) */
main.error h2 { margin-top: 0; }
main.error h1 { margin-bottom: .75rem; }
main.error p { color: var(--muted); margin: 0 0 2rem; }

@media (max-width: 30rem) {
  dl { grid-template-columns: 1fr; gap: 0; }
  dd { margin-bottom: .75rem; }
}