JSFiddle - React, Tailwind, and code Playground

HTML

<div id="wrap" style="border: solid 1px green; width: 100%;">
        <span style="border: solid 1px blue; width: 100%; display: block;">z</span>
    </div>

CSS

span:after {
    display: inline-block;
    content: " ";
    width: 0;
    height: 0;
    border-left: 5px solid transparent;
    border-right: 5px solid transparent;
    border-top: 5px solid #aaaaaa;
    padding-top: 2px;
    position: relative;
}