<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0//EN">
<html>
<head>
<style>
.table {
  background-color: purple;
  color: white;
  height: 100%;
}

.outer {
  border: 3px solid red;
  margin: 1em;
}
</style>
</head>
<body>

<table class=outer>
  <tr><td><table class=table><tr><td>Table One</table><table class=table><tr><td>Table Two</table></td></tr>
</table>

<table class=outer>
  <tr><td><div class=table>Div One</div><div class=table>Div Two</div>
</table>