Test Playground

index.css

#mydiv h1 {
	color:blue;
}

index.html

<div id="mydiv">
	<h1>Hello World!</h1>
</div>
<script src="https://code.jquery.com/jquery-3.4.1.min.js"></script>

index.js

$(document).ready(function () {
	$('#mydiv').on('click', function (e) {
		alert('hey that tickles!');
	});
});

playground.json

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