I am not sure what you are after and a link to your site would also help, but maybe something like this could get you in the right direction
It is just a div with a border around the image link. Adjust the height and width to your image size. Try this first and later you might want to reference the css elsewhere instead of inline.
<div style="border:1px solid black; padding: 3px; width:600px; height:400px">