JSFiddle - React, Tailwind, and code Playground

HTML

<div id="cool1" class="cool">Cool 1</div>
<div id="cool2" class="cool">Cool 2</div>

CSS

.cool:after{
    display: inline-block;
    border-right: 6px solid transparent;
    border-bottom: 6px solid red;
    border-left: 6px solid transparent;
    content: '';
}



#cool2:after{
    content:none;
}