JSFiddle - React, Tailwind, and code Playground

HTML

<div class="bar"></div>
<div class="button">click me</div>

CSS

.bar {
    
    height: 15px;
    width:0%;
    background-color: red;
}

JavaScript

var obj = {
    bar: {
        el: $('.bar'),
        width: el.outerWidth()
    },
    page: {
        el: $(window),
        width: el.width()
    }
}

//console.log(obj);

$('.button').click(function(){

    
});