JSFiddle - React, Tailwind, and code Playground

HTML

<article>
    <p>test</p>
</article>

CSS

.focus article {
    color: green;
}

JavaScript

var	bod     = document.getElementsByTagName('body')[0],
    article = document.getElementsByTagName('article')[0];


window.addEventListener("load",function(){
    bod.classList.remove('loading');
},false);


article.addEventListener("mouseover",function() {
    bod.classList.add('focus');
},false);

article.addEventListener("mouseout", function() {
    bod.classList.remove('focus');
}, false);