svg with hole code example

Example: cut holes in svg shapes

<div style="background: #ddf">
  <svg width="200" height="200">
    <defs>
      <mask id="hole">
        <rect width="100%" height="100%" fill="white"/>
        <circle r="50" cx="100" cy="100" fill="black"/>
      </mask>
    </defs>

    <circle id="donut" r="100" cx="100" cy="100" mask="url(#hole)" />

  </svg>
</div>