<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>CSS Reference: ::marker pseudo elements styled with 'content' property and display:flex</title>
<link rel="author" title="Mats Palmgren" href="mailto:mats@mozilla.com">
<style>
body { margin-left: 100px; }
li {
  list-style-type: 'FAIL';
  background: grey;
}
li::marker {
  content: "X";
  display: block;
  width: 100px;
  text-align: start;
  background: lime;
}
span { font-size: 32pt; }
</style>
</head>
<body>
<ol><li></li><li>B</li><li><span>C</span></li></ol>
</body>
</html>