css - margin: 0 auto not centering? - Stack Overflow
So, from left to right you see the padding or margin on the body element (margin in this case as it is Chrome), then the border for the div, then the 400px of width, then the next border, and then the window edge as there isn't any more space to render the body's right margin. Share Improve this answer Follow answered Oct 30, 2010 at 20:18 Quentin