Gwen Stefani is on fire these days ... in more ways than one.

The 45-year-old recently debuted her music video for her latest single, 'Spark The Fire,' while at the same time showed off her newly dip-dyed locks in the colors black, red, and orange, resembling a flame.

The singer showed off her new look at the KIIS FM's Jingle Ball 2014, where she performed her single along with 'The Voice' coach, Pharrell Williams.

"OMG OMG thank you for having me #KIISJingleBall. @Pharrell so fun to #SparkTheFire with you!" she wrote on Twitter