JSFiddle - React, Tailwind, and code Playground

HTML

<div></div>

CSS

div{
    width: 7em;
    height: 7em;
    background: red;
    border: .1em orange solid;
    position: relative;
}

JavaScript

var div = document.getElementsByTagName("div")[0],
    limite = prompt("Distancia:"),
    x = 0,
    fn = function(){
        x += 5;
        if (x <= limite){
            div.style.top = x + "px";
            div.style.left = x + "px";
        }
    };

setInterval(fn, 1000);