Katy Perry hit the town looking bright and colorful to celebrate her dad Keith Hudson's birthday at Dominick's restaurant in West Hollywood.

The sexy songstress rocked a red floral-print dress, bright strappy shoes and a black leather jacket ... all while sporting her purple locks.

This fun and flirty look is so different from her flapper get-up she wore to this week's City of Hope Spirit of Life Awards Gala at MOCA in LA.

See more of Katy's cheerful look in our gallery below.