JSFiddle - React, Tailwind, and code Playground

by Palpatim

HTML

<button>Click</button>

CSS

html {
    background: url(http://img1.wikia.nocookie.net/__cb20120203162541/pataponfanfiction/images/1/1f/Chrome-logo.png) no-repeat center center fixed;
    -moz-background-size: 100%;
    -o-background-size: 100%;
    -webkit-background-size: 100%;
    background-size: 100%;

    -moz-transition: background-size 2s ease-in-out;
    -o-transition: background-size 2s ease-in-out;
    -webkit-transition: background-size 2s ease-in-out;
    transition: background-size 2s ease-in-out;
}
html.loaded {
    -moz-background-size: 120%;
    -o-background-size: 120%;
    -webkit-background-size: 120%;
    background-size: 120%;
}

JavaScript

$(function () {
    $('html').toggleClass('loaded');
});