three.js/threejs/lessons/resources/threejs-primitives.css

div[data-primitive] {
    padding-bottom: 2em;
    border-bottom: 1px solid #888;
    margin-bottom: 2em;
}
div[data-primitive] .pair {
  display: flex;
  align-items: center;
  margin-bottom: 1em;
}
div[data-primitive] .shape {
  flex: 0 0 auto;
  width: 200px;
  height: 200px;
}
div[data-primitive] .desc {
  word-wrap: break-word;
  padding: 1em;
  min-width: 0;
}
div[data-primitive] .desc code {
  white-space: normal;
}
@media (max-width: 550px) {
  div[data-primitive] .shape {
      width: 120px;
      height: 120px;
  }
}
div[data-primitive] .desc {
  flex: 1 1 auto;
}