<!DOCTYPE html>
<html>
<head>
<script src="/lib/jquery-1.12.2.min.js"></script>
<script>
$(document).ready(function(){
$("button").click(function(){
$("#span1").text($(window).width());
$("#span2").text($(document).width());
});
});
</script>
</head>
<body>
<p>The width of this window is <span id="span1">unknown</span> px.</p>
<p>The width of this document is <span id="span2">unknown</span> px.</p>
<button>Return the width of the window and document elements</button>
</body>
</html>