sections on page keep moving around

Hi,

I am having trouble with sections on my homepage moving around when you change the browser size or resolution. When you increase the resolution size or make everything a little smaller in the browser (on a Mac, it’s command-, or command+ if you go the other way), the sections to the right (Shows and News) of the main area move below the main area instead of staying to the right.

Any help would be greatly appreciated! Here is my index.php code:

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