Photo Frame

Hi, photos have a nice frame at this theme when they don't have a description. When there is a description though, it looks like a Polaroid photo in WordPress. On the actual site you can hardly see the grey background and there is a line in front of the description. Have a look here: http://www.aussiebuschfunk.net/wildblumen-im-suedwesten-australiens-2/ How can I change it? And is there a way that even the photos with description have a simple frame like the ones without? I would be very grateful for any help! Thanks and kind regards, Irina