<!DOCTYPE html>
<link rel="stylesheet" href="test-common.css">
<style type="text/css">
  @counter-style a {
    system: extends lower-alpha;
    range: 1 2;
    range: 1;
    range: 3 1;
    range: xx yy;
  }
</style>
<ol style="list-style-type: a">
  <li><li><li><li><li>
</ol>