JSFiddle - React, Tailwind, and code Playground

HTML

<div id="changecolor2"></div>

CSS

#changecolor2 {
    height: 100px;
    width: 100px;
}

JavaScript

var colors = ["red", "blue", "yellow", "green", "orange", "black", "cyan", "magenta"];
var colorIndex = 0;
function changeColor() {
    var col = document.getElementById("changecolor2");
    if( colorIndex >= colors.length ) {
        colorIndex = 0;
    }
    col.style.backgroundColor = colors[colorIndex];
    colorIndex++;
}

window.onload = changeColor;