How to stop the horizontal scroll bar from showing when window is resized? -

i have website http://www.claybrookeanimalfeeds.co.uk/index.php want able keep content in middle of page. i've got of content stays in same place when window re-sizes, problem when re-size window half size of screen, horizontal scroll bar appears when move scroll bar right, there's nothing there , it's blank space.

is there anyway can make content stays in same place without scroll bar appearing when re-size window?

instead of using percentages widths containers, use pixel value.

example: #content { width: 800px }