<!DOCTYPE html>
<meta charset="utf-8">
<title>display: block math and inline math on pseudo elements (reference)</title>
<style>
  .inline::before { content: 'math'; display: inline; }
  .inline::after { content: 'math'; display: inline; }
  .block::before { content: 'math'; display: block; }
  .block::after { content: 'math'; display: block; }
</style>
<p>Test passes if SPAN and DIV are respectively surrounded by inline and block
  "math" text.</p>
<div>
  <span class="inline">SPAN</span>
</div>
<div>
  <span class="block">DIV</span>
</div>