JSFiddle - React, Tailwind, and code Playground

HTML

<div id="outer" lang="es">
    <div id="inner"></div>
</div>
<pre id="output"></pre>

JavaScript

var output = document.getElementById('output');

output.innerText += 'outer lang: "' + document.getElementById('outer').lang + '"\n';

output.innerText += 'inner lang: "' + document.getElementById('inner').lang + '"\n';