I'm packing this afternoon for a weekend trip. We are attending an engagement BBQ tomorrow evening. It seems like a very casual event (invitations were printed at home, there is a hand drawn map on the back, and no dress code was specified.) Temps will be in the 50s. I'm just at a loss for what to put in my bag. I'm thinking jeans, flats and a dressy top with a cardigan would do the trick?