What is this? How do i do it?

Hey. I have seen it done.. How exactly is this done???
What i mean is when you put your mouse over a spot .. it will change colours...

like you wll see what i mean.. the one part that had the mouse over it is purple..

Thanks guys

[Admin]

It's just HTML code, doesn't have anything to do with vBulletin.
Edit your templates and add it.

Also please enter your license information in your profile (as you've been already asked).