I found this gradient in Pixlr by accident and I really liked it so I made it a skin.
(Also in case you decide to use this and you want to make a matching OptiFine cape or something, the two ends of the gradient are FC00FF for the pink and 0DCEDF for the blue. This won't work perfectly for the "KiwiWick 2.0" skin since I used the gradient from the optifine cape preview on the website for the gradient on this skin. It's actually a pretty useful tool for this.)