<!DOCTYPE html>
<html>
  <head>
    <style>
      span.b { display: inline-block; height: 20px; }
      span.break { display: block }
    </style>
  </head>
  <body>
    <span style="background: url(blue-16x20-green-16x20.png)">
      <span class="b" style="width: 24px"></span><span class="break"></span>
      <span class="b" style="width: 24px"></span>
    </span>
  </body>
</html>