JSFiddle - React, Tailwind, and code Playground

HTML

<div></div>

CSS

div{
    width: 100px;
    height: 100px;
    background-color: red;
    border-radius: 100%;
    position: relative;
}
div:before{
    content: "";
    width: 100%;
    height: 110%;
    background: gray;
    position: absolute;
    left: 5px;
    top: -5%;
    border-radius: 100%;
}