Check this fiddle out: http://jsfiddle.net/3PduX/18/
I put display:block
to the span, which i think may have been what you missed.
Radu Chelariu's idea was even better though. I smashed a working example together without having to use the extra span, check it out here: http://jsfiddle.net/3PduX/22/
It uses the :after
pseudo element.