<html xmlns="http://www.w3.org/1999/xhtml">
  <head>
    <style>
      @font-face
      {
          font-family: Ahem;
          src: url(../fonts/Ahem.ttf);
      }
      math {
          font: 25px Ahem;
      }
    </style>
  </head>
<body>
  <math xmlns="http://www.w3.org/1998/Math/MathML">
    <mfrac linethickness="100%">
      <mn>1</mn>
      <mn>2</mn>
    </mfrac>
  </math>
</body>
</html>