Good evening Craig and welcome to the Events Calendar forum!
Thank you for your interest in our products.
We’ll be glad to answer your questions.
The short answer is yes. However, this is not a built-in feature.
You would have to do a template customization to achieve this result.
You might want to read our Themer’s guide to get a sense of how that works.
Basically you will want to add CSS classes to the different events based on the date and your rules.
Once that is done you will only need to assign the right colour to each of these classes.
Let me know if that helps.
Have a great day!
Geoff B.