JSFiddle - React, Tailwind, and code Playground

HTML

<table width="100%" cellspacing="10">
  <tr>
    <td width="50%" bgcolor="red"></td>
    <td width="50%" bgcolor="red"></td>
  </tr>
  <tr>
    <td width="50%" bgcolor="red"></td>
    <td width="50%" bgcolor="red"></td>
  </tr>
</table>

CSS

body {
    margin: 0;
}

JavaScript

$('td').height($('td').width());