<!DOCTYPE html>
<html>
  <head>
    <style>
      tr {
        font: medium / 1000 cursive;
      }

      :only-of-type {
        border-image: repeating-linear-gradient(45deg, blue, red) space 1% / 1pt auto;
      }
    </style>
    <script>
      o1 = document.createElement('tr');
      o2 = document.createElement('th');
      o3 = document.createElement('rt');
      document.documentElement.appendChild(o1);
      o1.appendChild(o2);
      o2.appendChild(o3);
    </script>
  </head>
</html>
