<!doctype html>
<style>
 body { margin: 0 }
</style>
<svg width=200 height=200 viewbox="0 0 200 200">
  <rect fill="purple" x=0 y=0 width=100 height=100 />
  <rect fill="blue" x=0 y=0 width=50 height=50 />
</svg>
