JSFiddle - React, Tailwind, and code Playground

HTML

<div id="dot"></div>

CSS

#dot {
    background-color: green;
    width: 10px;
    height: 10px;
    border-radius: 5px;
    position:absolute;
    top: 200px;
    left: 200px;
}

JavaScript

var center_x = 150,
    center_y = 150,
	r_x = 120,
	r_y = 80,
	i = 3,
    y = r_x*Math.cos(i) + center_x,
    dot_el = document.getElementById('dot');
console.log(y+" "+i);
function dot() {
    i+=0.01;
    var y = r_x*Math.cos(i) + center_x,
        x = r_y*Math.sin(i) + center_y; 
    if  (1>0) {
        console.log(y+" "+i);
    }
    dot_el.style.top = x+'px';
    dot_el.style.left = y+'px';
}

setInterval(function(){
    dot();
},10);
//