:root {
  color-scheme: light dark;
}

body {
  background-color: light-dark(#ffffff, #151515);
  color: light-dark(#151515, #d4d4d4);
  font-family: "Times New Roman", Times, serif;
  line-height: 1.4;
  margin: auto;
  max-width: 72ch;
  overflow-y: scroll;
  padding: 1rem;
}

a {
  color: light-dark(#00598a, #81a2be);
  text-underline-offset: 0.25rem;
}

footer {
  display: flex;
  justify-content: space-between;
  margin: 1rem 0;
}

.next,
.previous,
.placeholder {
  flex-grow: 1;
}

.hidden {
  visibility: hidden;
}

header ul {
  display: flex;
  list-style-type: none;
  padding: 0;
}

header ul li {
  padding-right: 1ch;
}

iframe {
  aspect-ratio: 16 / 9;
  border: none;
  display: block;
  width: 100%;
}

img {
  display: block;
  max-width: 100%;
}

pre {
  background-color: light-dark(#f4f4f4, #222222);
  overflow-x: auto;
  padding: 1rem;
}