How to set the color of series in a graph

Hi,

I am creating two graphs with series highest and lowest and i have kept the color of series as Automatic in Graphs.

But both the graphs are giving different colors for series and i am not able to figure out how to make sure both graphs will have same set of colors for series.

I need to do this from UI only.

Please let me know how to make sure both graphs will use the same color for same series by keeping the fill option as Automatic.

Regards
Arti