devdocs/assets/stylesheets/pages/_erlang.scss

._erlang {
  @extend %simple;

  h3.code { @extend %code; }
  code.code { @extend %label; }
  .note { @extend %note; }
  .warning { @extend %note, %note-red; }
  .note .label, .warning .label { font-weight: $boldFontWeight; }
}