Only days after arch rival PepsiCo unveiled a new image for its flagship brands, Coca-Cola yesterday revealed a new design for its Diet Coke brand. It has been known since August that there were plans for a makeover for Coke Classic, Diet Coke and Sprite. However, a Coke spokeswoman yesterday said that there are now plans to revamp packaging for the whole cola range, including caffeine-free colas and colas with lemon flavouring. The new look brands will be available from next year, she said.