JSFiddle - React, Tailwind, and code Playground

HTML

<html>
    <head>
        <script language="javascript" type="text/javascript">
            function addHeading(node, text) {
            var newNode=document.createElement("h1");
            var text=document.createTextNode(text);
            newNode.appendChild(text);
            node.appendChild(newNode);
            }
        </script>
    </head>
    
    <body>
        <div onmouseover="addHeading(document.body, 'Header added')">
            Hola!
        </div>
    </body>
</html>