Users with # Posts see Certain style

[SouthernTn]

Whats the code to make it where, users who have made a certain amount of posts see a certain style set?

thanks

[who is chris c]

you can use it as a promotion that after x posts you get new usergroup with new style

[SouthernTn]

Inside the usergroups I dont see where I can have that usergroup use a certain style