:root {
  color-scheme: light;
  --background: #fff;
  --text: #222;
}
@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --background: #000;
    --text: #fff;
  }
}
body { 
  max-width: 48em; 
  margin: auto; 
  line-height: 1.5; 
  padding: 0.8em; 
  word-wrap: break-word; 
  background: var(--background);
  color: var(--text);
}
.header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: 0;
}
.header h2 {
  margin: 0;
}
header + hr {
  margin-top: 0.2rem;
}
a.nav-title,
a.nav-title:visited,
a.nav-title:hover,
a.nav-title:active {
  color: inherit;
  text-decoration: none;
  background: none;
  border: 0;
  box-shadow: none;
}