Um..your CSS is leaking onto the miscellaneous page, to stop that, you have to put it underneath the cut.

In case you're unsure of how to do this

Click 'edit' < Pretty obvious
There is a button on the right hand side that says 'Split Summary...'
Two Boxes for the body will now be there.
You need to make sure that the code is in the bottom box.
I generally just chuck in a CSS warning there, and then press don't show in full view, but you can put in there whatever you want.