* Justin * variable requires type-hint or initialization - Oh * Justin *Plz Help

Getting error:
Using mdotedot's HTML5 extention - variable requires type-hint or initialization

How can I implement this in HTML5: [or any other way]
<div id="Layer1" style="position:absolute; left:1px; top:1px; width:179px; height:252px; z-index:1">
  <iframe src="http://www.bing.com" style="width: 20%; height: 300px"></iframe></div>