Reminders CSS

I have been trying to update the CSS for the overdue class so that any reminder that is overdue will show with a different background but unfortunately I have not been successful so far. Has anyone ever done this before or at least point me in the right direction? Thanks.

Eric O’Brien
System Administrator
BioReference Laboratories, Inc.
Phone: 201-791-2600 x 8310
Cell: 551-486-8925
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