JSFiddle - React, Tailwind, and code Playground

HTML

<div id="googleframe"><iframe id="googleseo" src="http://fiddle.jshell.net"></iframe></div>

JavaScript

var seoFrame = document.getElementById('googleseo');
var elem = (seoFrame.contentDocument||seoFrame.contentWindow.document).documentElement;
elem.getElementsByTagName('body')[0].scrollTop = 300;