OK, so I guess it meets the challenge but only because you manipulated it either with a purple filter or in an image editing software. This is not a natural looking sunset becuse sunsets or sunrises do not naturaly look like this. It feels to me that you made it this way just because the challenge was "Purple". I don't know if I'm explaning myself clearly, but, although I think this is good photo overall, I think you tried to shoehorn it into the challenge. BTW, your horizon is tilted, this isn't visually appealing.