JSFiddle - React, Tailwind, and code Playground

by swfour

HTML

<style>
    .foo {
        background: red
    }
    span {
        font-size:30px
    }
</style>
<div style="color: blue"> <span id="bar" class="foo">hello</span>

</div>
<div id='output'></div>

CSS

background-color: red;
 color: blue;
 font-size: 30px;

JavaScript

var styles = window.getComputedStyle(document.getElementById('bar'));
styles = "background-color:" + styles['background-color'] + ";color:" + styles['color'] + ";font-size:" + styles['font-size'] + ";";
document.getElementById('output').innerHTML = JSON.stringify(styles);