How can I get rid of the blank space under the website?

OK, so im working on this website for a friend. The homepage looks pretty good but im having a problem with the 4 pages that are linked at the top. Every time I click on them and they load but there is a big blank space at the bottom of the page. Its not a huge deal but I think it looks funny. Anyone have any idea whats wrong with it? Did I mess up a line of code (probably), and if so, where would that line of code be?

I want the page to stretch all the way to the bottom of the browser windows. Any help would be great, even if you can just point me in the right direction.开发者_如何学JAVA Thanks!

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You should try changing the main table's height from 86% to 100%.