Why does:
width: 98%; max-width: 1140px;
do the same as
width: 1140px; max-width: 98%;
The first one make
Probably in your first case 98% is equal or more than 1140px, so it will stick at 1140px.
In the second case of course, the width is 1140px, so it will stick to 1140px, and the max-width become useless.
Update Try it here http://jsfiddle.net/