How to set fa fa-palette icon as a background for an input type="color" in html/css?

Question

I'm creating a paint app with html and I added a feature - adding your own colors with input type="color", but its default styling is really bad, so worked on it, but the last step is to make its background-image fa fa-palette icon. I tried background-image, background, placeholder, but I can't think of any other ideas. Could you help?