Bug in css file?

I am trying to combine the front.css file using the “less” compiler, but it complains about the empty brackets, ie {}.

part including this:

span iframe{max-width:none !important;z-index:10000000 !important}{} li.the_champ_facebook_like{width: 89px}.

This code is not actually doing anything right, but seems to break the compiler?

Cheers.

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