Wrap your charts in a container and this will give you the flexibility to adjust the size of the chart when the screen changes.
Also specify the width of your shell and make it float to the left so that the charts are located side by side.
Here is an example: http://jsfiddle.net/ZrTux/9/
.chart-wrapper { float: left; padding-bottom: 40%; position: relative; width: 45%; }
Satya
source share