JSFiddle - React, Tailwind, and code Playground
by Bilal AFSAR
HTML
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css">
<span class="btn-overlay" disabled>
<button id="btnTest" class="btn btn-primary">
<span class="fa fa-certificate"></span>
Test
<i class="fa fa-refresh fa-spin"></i>
</button>
</span>
CSS
.btn {
position: relative;
}
.btn-overlay {
position: absolute;
padding: 0;
top: 0;
left: 0;
width: 100%;
height: 100%;
background-color: #ffffff;
opacity: 0.1;
transition: opacity .5s;
}