JSFiddle - React, Tailwind, and code Playground

HTML

<div>
    <p>
        <span>
            <label>no good, because not the last</label>
        </span>
    </p>
    <p>
        <span>
            <label>good</label> <!-- This one should be selected -->
        </span>
    </p>
    <p>
        <label>no good, because is not inside of a span</label>
    </p>
</div>

JavaScript

Ext.select('div > p > span > label:last').setStyle('background', 'red');