I made this jsfiddle:
http://jsfiddle.net/q5keu9p0/1/
1- What I want is the pie graphs to be responsive. You can see when you change the window screen the pie doesn't return to the original size when the screen was opened.
2- Is there a way to the height of the chart to be the sabe as the weight of the pie itself? In this exemple you can see the height of the graph to be very high compared to the weight of the graph.