 margin-box with border-radius.">

<style>
  .clipped {
    width: 50px;
    height: 50px;
    background-color: green;
    clip-path: margin-box;
    border-radius: 10px;
    /* This outline draws far outside the margin box and should be partially clipped. */
    outline: 200px solid green;
    margin: 50px;
    /* Disables margin collapsing. */
    float: left;
  }
</style>
<!--
  Spec: If the ratio of border-radius/margin is less than 1, and margin is
        positive, then the margin box corner radius i