JSFiddle - React, Tailwind, and code Playground

HTML

<div>
    <a href="#"></a>
</div>

CSS

div {
     width: 50px;   
     height: 50px;
     border: 1px solid green;
}

a {
     display: block;
     height: 100%;
     background: orange;  
     -moz-border-radius: 50%; 
     -webkit-border-radius: 50%;
     border-radius: 50%;
}

a:hover {
     background: green;   
}