devdocs/assets/stylesheets/pages/_mongoose.scss

._mongoose {
  padding-left: 1rem;

  > h1, > h2, > h3 { margin-left: -1rem; }
  > h2 { @extend %block-heading; }
  > h3 { @extend %block-label, %label-blue; }
  h4 { font-size: 1em; }
}