JSFiddle - React, Tailwind, and code Playground

HTML

<table id="t">
<td>1</td>
<td>2</td>
<td>3</td>
<td>3</td>
<td>2</td>
<td>1</td>
</table>

JavaScript

arr= document.getElementById("t").getElementsByTagName("td");
11	colors= ["", "blue", "red", "green"];
12	for (var i=0; i!= arr.length; ++i) {
13	 arr[i].style.background=colors[arr[i].innerHTML];
14	}