devdocs/assets/stylesheets/pages/_socketio.scss

._socketio {
  > h2 { @extend %block-heading; }
  > h3 { @extend %block-label, %label-blue; }
  > h2, > h3 { clear: both; }
  h4 { font-size: 1em; }

  .ezcol-one-half {
    margin: .5em 0 1.5em;
    float: left;
    width: 50%;
    padding-right: .5em;
    @extend %border-box;

    &.ezcol-last {
      float: right;
      padding: 0 0 0 .5em;
    }

    > h4 { margin: 0 0 1em; }
    > pre { margin: 1em 0 0; }
  }

  code { @extend %label; }
}