Create a red div cube with JS

Question

I need to create a div with:
width: 40px
height: 40px
background-color: red
by a js string, can you help me please?
This is my code:

var iDiv = document.createElement("div");
iDiv.setAttribute("id","place");
iDiv.style.backgroundColor = "red";
iDiv.style.width = "40px";
iDiv.style.height = "40px";

Answer 1

just add document.body.appendChild(iDiv);

if output error, put js code into <script> tag

Answer 2

thank you