We have made an update to enable you to colour the background of your calendar based on the location. This is related to our recent update which links rostered times to locations which you can read more about here.
To allocate a colour to a location go to Setup> Configuration> Locations. You can then click 'Edit' and use the colour picker to select the desired colour and click 'Save'.
The location is attached the diary roster in Setup> Roster. You can read more on how to set up your roster here.
Here is the end result: