Different calendars in different colors
It is possible to assign different colors to different calendars in order to make the display clearly arranged. To use this option you have choose the scheme Custom Colors in the menu View at top right.
You may add a new calendar and afterwards you may click on the menu-icon beside the calendar. A menu will appear and you can choose the color to display the entries for this calendar.
If you view all my appointments you will see the entries in differnet colors.