Initially, it looks like you have an erroneous "div" terminator. The code below is right after your "body" tag. It shows the start of the "wrapper" div, followed by the "header" div. After the "header" div terminator, the "mainNav" div should start. But there is an extra "div" terminator that terminates the "wrapper" div. That puts all the rest of the code outside of the "wrapper" div. Unless there is another error down the line, removing that extra "div" terminator should allow the page to display correctly.
