My website was fine last night when I went to bed (I edited one page as I always do on Saturday night). This morning I can log in as administrator and load the homepage but it is totally blank - no menu, no dashboard, no nothing. It is a church website and since it is Sunday, many people will be trying to log in to listen to our recorded service so it is imperative that I get this fixed ASAP.

I've looked everywhere I can think of but can't see anything that is obviously wrong. Any help would be appreciated.