JSFiddle - React, Tailwind, and code Playground

HTML

<div class="circle"></div>

CSS

div.circle {
    width: 0;
    height: 0;
    padding: 20%;
    border-radius: 50%;
    border:0;
    margin:0;
    line-height:0;
    overflow:hidden;
    background-color: red;
}