is (top and bottom sides) are stretched." name="assert">

  <!--

  'stretch'
  The image is stretched to fill the area.

  https://www.w3.org/TR/css-backgrounds-3/#valdef-border-image-repeat-stretch


  'round'
  The image is tiled (repeated) to fill the area. If it does not
  fill the area with a whole number of tiles, the image is rescaled
  so that it does.

  https://www.w3.org/TR/css-backgrounds-3/#valdef-border-image-repeat-round

  -->

  <style>
  div
    {
      border: red solid 64px;
      borde