Creating full width (100% ) container inside fixed width container.
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For Making a full width containers (which spans 100% of window) inside a container which has a fixed width and aligned center like below picuture. I used following css now its done .box_short { position: relative; width: 100vw; left: 50%; margin-left: -50vw; } for deep knowledge you can follow this link http://jsfiddle.net/m1L6pfwm/2/