does it have color? is it a good base to apply under any color eyeshadow?

It has color, but once it is applied evenly over the eyelids (I use a separate brush to pat it in evenly over my eyelids and above my eyes, to my eyebrows), you end up with a sheer, light-toned base. I have used it for years, and I have not found an eyeshadow that it doesn't work with. Brands in my collection include UD, Pat McGrath, ABH, Jeffree Star, Melt, Colorpop, and many others.