css/css-fonts/font-size-adjust-units-001.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>CSS Fonts Test: font-size-adjust effect on font-dependent units</title>
<link rel="author" title="Jonathan Kew" href="mailto:jkew@mozilla.com">
<link rel="help" title="2.6 Relative sizing: the font-size-adjust property"
      href="https://drafts.csswg.org/css-fonts/#font-size-adjust-prop">
<link rel="help" title="6.1.1. Font-relative Lengths: the em, rem, ex, rex, cap, rcap, ch, rch, ic, ric, lh, rlh units"
      href="https://drafts.csswg.org/css-values-4/#font-relative-lengths">
<meta name="assert" content="Font-relative units like ch and ex are affected by font-size-adjust,
because they are derived from metrics of the _used_ font.">
<link rel="match" href="font-size-adjust-units-001-ref.html">
<link rel="stylesheet" type="text/css" href="/fonts/ahem.css" />
<style>
  div {
    margin: 10px;
    font: 100px/1 Ahem;
    font-size-adjust: 0.8;  /* this matches Ahem's ex-height metric */
    background: orange;
    width: 2ch;
    height: 1ex;
  }
  #test1 {
    background: blue;
    font-size-adjust: 0.4;
    width: 4ch;
    height: 2ex;
  }
  #test2 {
    background: blue;
    font-size-adjust: 1.6;
    width: 1ch;
    height: 0.5ex;
  }
</style>
<body>
  <p>Test passes if the blue rectangles are both the same size as the orange one.</p>
  <div id="test1"></div>
  <div id="test2"></div>
  <div></div>
</body>