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;
}

div[data-primitive] .input {
  display: inline-block;
  user-select: none;
}
div[data-primitive] .input::before {
  content:" ";
}
div[data-primitive] .input input[type=range] {
  width: 200px;
}
div[data-primitive] .input>div {
  position: absolute;
  display: inline-block;
}
div[data-primitive] .input input {
  position: absolute;
}
div[data-primitive] .input input[type=text] {
  background: #444;
  color: white;
  border: none;
  padding: 3px;
}

@media (max-width: 600px) {
  div[data-primitive] .input>div {
    right: 0;
  }
  div[data-primitive] .input input {
      opacity: 0.2;
      right: 1em;
  }
}

@media (max-width: 550px) {
  div[data-primitive] .shape {
      width: 120px;
      height: 120px;
  }
}
@media (max-width: 450px) {
  div[data-primitive] .pair {
    flex-direction: column-reverse;
  }
  div[data-primitive] .shape {
    margin: 0 auto;
    width: 100%;
  }
}
div[data-primitive] .desc {
  flex: 1 1 auto;
}