CSS: How can I get rid of the default window “padding”? An element set to 100% width doesn't reach the window's borders

Question

So I have an element that is placed directly inside body:

    
Some stuff...
    Other stuff...

         


        

Answer 1

body has default margins on all browsers, so all you need to do is shave them off:

body {
    margin: 0;
    text-align: center;
}

You can then remove the negative margins from #header.