JSFiddle - React, Tailwind, and code Playground

by Jonathan Sampson

HTML

<div onmousemove="this.classList.add('bad')"></div>

CSS

div {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    background: green;
}

div::before {
    display: block;
    padding: 1em;
    color: white;
    font-family: "Segoe UI";
    content: "Screen should remain green during mouse-movement.";
    background: rgba(0,0,0,.85);
}

div.bad { background: red; }

JavaScript

document
    .querySelector( "div" )
    .removeAttribute( "onmousemove" );