Background color of individual activities on iWatch

The different activity rings on my iwatch are shown in different colors, e.g. the Move Goal is the red ring and the "page" with the specific information has a red background. Likewise, the green exercise ring has a green background for the detailed info. I find these colors annoying and would prefer the background to be black. It used to be black before one of the updates. Is there a way to change the background back to black or some color I might prefer?