Seeing as it's supposed to be the 4 elements, Fire, Wind, Water and Earth, I'd assume the red and purple one is fire because of it's flame like head, and the yellow/golden one is air because of it's wings on the sides of it's body
Yeah, but that's the thing about art, you don't have to stick to norm. Art is about how the artist views things, if she see's the wind as yellow and fire to have purple in it that's her own choice. Or as far as I know she could of been inspired to use those colours from something else, like an old story she read as a child. And anyway you can get purple fire, you just use a combination of chemicals I think you need potassium and some form of nitrate, and it's not like the wind actually has a colour itself anyway.