Why have I border around my site?

Hi!
here is the link where I have a big problem
http://www.code-elektronic.com/newsite/

on the left and top of the site I have some white border.
Can somebody figure out why and how to solve this?
I didn't wish this border.

I use in my css file for the main div element
margin-left: auto
margin-right: auto

I try to align the main div with the content in it to the center of the browser.

Some help please would be great...

Thnx.

Just add *{
margin:0;padding:0;
} into your CSS, to nullify all browsers specific default values of margin/padding from all elements. Or in your case body{margin:0;padding:0;} should also work.