JSFiddle - React, Tailwind, and code Playground

HTML

<div id="con">
    <div> 1 </div>
    <div> 2 </div>
    <div> 3 </div>
    <div> 4 </div>
    <div> 5 </div>
</div>

JavaScript

var con = document.getElementById('con');
var els = Array.prototype.slice.call(con.childNodes);
for (var i = els.length -1; i>=0; i--) {
    con.appendChild(els[i]);
}