Are you trying to change the color of a dashboard or, as shown below, add a label and color to the OneStream environment? If the latter, see below:
So how the dashboard in your screenshot is blue, i wanted to be a different colour.
I have gone to the section you are looking at however it is greyed out for me although i have admin access.
I do not believe you can change the OneStream inherit background color of blue. Even though it is greyed out, you should be able to uncheck the box next to those two items, then make your edit. It is greyed out for me too until I unchecked the boxes. Please note: those 2 items are per environment, not per app.
