I am positioning main-bar and side-bar with 70-30 ratio as under: JSFIDDLE
main-bar
side-bar
70-30
I recommend to go with float for these scenarios.
.main-bar, .side-bar{ margin:0; padding: 0; outline: 0; border:none; background:#CCC float: left; } .main-bar{width: 70%} .side-bar{width: 30%}