XF 2.2 How can I add primary and secondary groups as classes.

Hello, How can I separate the secondary user groups, that is, how can I give the class values.

How can I get secondary group User ids.

sample {{ $post.User.user_group_id ?: $user.user_group_id }}

What I want to do is if it's a birthday I don't want it to be promoted automatically I want to change the user color of the birthday person directly so I can change the color when it's his birthday