Our visual design encourages to choose among a set of safe colors:

• our groups use one out of 5 predefined colors, which is then used as background color for that group
• new groups configured by clients always have a white background. The client may however freely choose the color used for the group name. On click or touch start, as well as on hover, that color will then be briefly used as background color as well, but usually remains only visible against a white background else.

There are two reasons for this:

• we would like to distinguish between client groups and Magnolia groups
• there are not many colors that work nicely against the green background the Apps screen uses

We may also want to allow a customer to pick arbitrary colors for client groups, if they want to, but the configuration should allow the use of symbolic names for safe colors.

Found in the "App framework" section of the "How to build a Magnolia 5 app" chapter in the draft of the Magnolia 5 book.