devdocs/assets/stylesheets/pages/_react_native.scss

._react_native {
  @extend %simple;

  .deprecated { @extend %note, %note-orange; }
  .deprecatedTitle { font-weight: var(--boldFontWeight); }

  span.platform { float: right; }
  span.propType, span.platform { font-weight: normal; }

  .label {
    display:inline-block;
    font-size:.85rem;
   }
   .label::before {
     content: "[";
   }
   .label::after {
     content: "]";
   }
}