The code is not on Kofi, it's a basic F2U CSS that can be copied out from the page -- the HTML used in the CSS example is a code that can be purchased however, you may be mixing these two codes up.
I'm not sure why that would be, if you could take a screen cap of where you're pasting it into and what the code looks like I could try to figure out what the issue might be.
F2U Custom World CSS's Comments