JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.4.0/css/font-awesome.min.css">
<span>
<i class="fa fa-minus"></i>
</span>

CSS

span{
    background-color: yellow;
     font-size: 400px;
}
i { 
    background-color:lightgray;
    }