JSFiddle - React, Tailwind, and code Playground

HTML

<div class="object"></div>

CSS

.object {
        width: 100px;
        height: 100px;
        position: relative;
        top: 0px;
        left: 0px;
        background-color: white;
        border: 1px solid;
}

JavaScript

function RGB2HTML(red, green, blue)
{
    var decColor = blue + 256 * green + 65536 * red;
    return '#' + decColor.toString(16);
}


window.onload = function(){   
    var currentColor='white';
    var red = 256;
    var green = 256;
    var blue =256;
    var left = 0;
    var top = 0;
    setInterval(function(){
        top += 10;
        left += 10;
        red -= 10;
        green -= 10;
        blue -= 10;
        $('.object').css ({
            'top' : top,
            'left' : left,
            'background-color': RGB2HTML(red, green, blue)
        });
    }, 1000);
};