Board Thread:Support Requests - Designing Your Wiki/@comment-4591506-20130821061857

I have a CSS code Link: http://www.cssrex.com/tips-tricks/how-to-create-3d-text-using-css3/ and I'm trying to figure out how to make the code work (where to put it). The code for the CSS is

So, If anyone knows, please reply and tell me how to make it work. 