:root {
  color-scheme: light dark;
  --bg: #ffffff;
  --fg: #171717;
  --muted: #666666;
  --border: #dddddd;
  --surface: #f7f7f7;
  --link: #2457c5;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #111111;
    --fg: #eeeeee;
    --muted: #aaaaaa;
    --border: #333333;
    --surface: #181818;
    --link: #8ab4f8;
  }
}

* {
  box-sizing: border-box;
}

html {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.65;
  background: var(--bg);
  color: var(--fg);
}

body {
  margin: 0;
}

main, header, footer {
  width: min(760px, calc(100% - 40px));
  margin-inline: auto;
}

header {
  padding: 56px 0 20px;
  border-bottom: 1px solid var(--border);
}

main {
  padding: 36px 0 56px;
}

footer {
  padding: 24px 0 40px;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.92rem;
}

h1, h2 {
  line-height: 1.25;
}

h1 {
  margin: 0 0 8px;
  font-size: clamp(2rem, 7vw, 3rem);
}

h2 {
  margin-top: 36px;
}

p, li {
  max-width: 72ch;
}

a {
  color: var(--link);
}

nav {
  display: flex;
  gap: 18px;
  flex-wrap: wrap;
  margin-top: 18px;
}

.card {
  padding: 20px 22px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
}

.meta {
  color: var(--muted);
}