I'm encountering an issue with a new website I'm working on. This is my first time utilizing SVG's. Essentially, I need to crop a circle that remains centered on the page from my image to reveal the image beneath the element. Although I attempted to manipulate my clipping and everything seemed fine, I am unable to pinpoint the error in my mask code. Here is the link to a quick fiddle that I created. Thanks!
<div class="bg-gradient">
<img src="http://www.redhdwallpapers.com/wp-content/uploads/2014/05/red-background-6.jpg"/>
</div>
<svg version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<defs>
<mask id="mask">
<circle cx="50%" cy="50%" r="45%" fill="none" />
</mask>
</defs>
</svg>