<!DOCTYPE html>

  <meta charset="UTF-8">

  <title>CSS Reference File</title>

  <link rel="author" title="Gérard Talbot" href="http://www.gtalbot.org/BrowserBugsSection/css21testsuite/">

  <style>
  ruby
    {
      background-color: lightblue;
      font-size: 40px;
    }
  </style>

  <ruby><rbc>B<ruby>&#8203;<rt>A</rt></ruby></rbc></ruby>

  <!--

  &#8203; or &#x200B; is the entity reference for zero-wide space.

  MathML uses the entity name &ZeroWidthSpace; for this character.

  -->
