JSFiddle - React, Tailwind, and code Playground

HTML

<p>Opacity changing</p>

CSS

p {
    background-color:blue;
    color:white;
}

JavaScript

$(document).ready(function() {
    $("p").animate({
        opacity: 0.5
    }, 1500).
    animate({
        opacity: 0.9
    }, 1500);;
});