Ability to Customize Colors of Charts and Graphs

I’m most interested in the “Graphs” section under “Charts” to get a good view of my sleeping pattern over a period of time, but the current scheme (dark blue on grey) seems difficult to see (I rarely remember to activate the app on my Pebble, so the green doesn’t show up often on my graph). It would be nice if you could customize the colors of the bars (e.g. instead of dark blue and green, you could change it to, say, orange and red, or whatever color combination works for you)