Well, my best guess is that your background images are further down than you think, meaning the body is lengthening to accommodate them... just saying this because I noticed that you are indeed pulling the images up pretty high (-703px for instance for the "top" coord on one of the images). Try moving the "default" position of the images to a much smaller number so that they are onscreen all the time, not only when you mouse over. Then you'll see if any of them are pushing the bottom of the page down. Then you can reposition their vertical position, and then move them back off-screen. You have some funny things in your css too: #header { margin: 0 auto; height: 50px; text-align: center; } The margin: 0 auto won't do anything unless you give #header a width (be default, as a block, it is 100% wide of its parent, the #container), so I'm thinking that's why you have text-align: center for centering. So, you could simply remove margin: 0 auto from a lot of your declarations-- they are generally useless without a stated width. PS awesome title : )