Extra black space when embedding webplayer game

When I embed my web player game in my site, there is extra black space to the right of the game.

Im am not sure if this is Unity Free creating a sort of water mark in my game of if it is because my game did not fill up the entire game view in my editor.

If it is a water mark I suppose there is nothing that I can do to get rid of it, but if it is because I didn't fill the game screen that's another story.

Any suggestions about what I should do will be helpful. Thanks.