JSFiddle - React, Tailwind, and code Playground

HTML

<button id="button">Click Me</button><br/><br/>
<div id="myDiv"></div>

CSS

#myDiv {
    background-color: blue;
    width: 375px;
    height: 375px;
}

JavaScript

$(document).ready(function() {

    $.easing.myEasing = function (x, t, b, c, d) {
        return c*((t=t/d-1)*t*t*t*t + 1) + b;
    }

    $("#button").click(function() {
        $('#myDiv').slideToggle(
            3000, 
            'myEasing'
        );
    });

});