How to call a specific site style based on the date of an event

[YLP1]

I have searched just about everywhere and could not find a modification similar to the example below. I wish I had the talent to do the coding myself but alas...newbie I am. I did give it a whirl but made a big mess. Does anyone know of a current mod or know what code I would have to enter and where to achieve the following:

example 1: If you have birthdays turned on and you have a birthday site style, is there a way for the birth month & day (not year) to use an assigned birthday style?

example 2: How about any major holiday like New Years eve & day would tie into a New Years Skin style. Or other major holidays.

Thanks in advance for any insight on the above.