JSFiddle - React, Tailwind, and code Playground

HTML

<body id="styleMe">
    <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Aperiam unde culpa asperiores exercitationem provident deserunt quasi voluptas voluptate officiis rem maxime amet hic at natus molestias nesciunt explicabo cumque beatae.</p>
    <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Aperiam unde culpa asperiores exercitationem provident deserunt quasi voluptas voluptate officiis rem maxime amet hic at natus molestias nesciunt explicabo cumque beatae.</p>
    <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Aperiam unde culpa asperiores exercitationem provident deserunt quasi voluptas voluptate officiis rem maxime amet hic at natus molestias nesciunt explicabo cumque beatae.</p>
</body>

JavaScript

var randomBackground = function(cssId) {
    var backgrounds = [
        'http://www.placehold.it/1024x768',
        'http://www.placehold.it/800x600',
        'http://www.placehold.it/640x480'
    ];
    
    document.getElementById(cssId).style.background = 'url('+ backgrounds[Math.floor(Math.random() * (backgrounds.length+1))] +')';
}('styleMe');