<svg width="100%" height="100%" xmlns="http://www.w3.org/2000/svg">
  <rect width="100%" height="100%" fill="lime"/>
  <!-- need tabindex for autofocus to work -->
  <rect x="10" y="10" width="300" height="90" fill="lime" autofocus="true"/>
  <style>
    rect:focus { outline: 2px solid blue; }
  </style>
</svg>