The hex color #a666b8 is a light color. The web-safe version is Hex
#9966CC. A complementary color is
#599947. The grayscale version is
#979797. A 20% lighter version of the original color is
#D999EB, and Hex
#733385 is the 20% darker color. If the color is saturated by 10%, you get
#A861BB. If the color is desaturated by 10%, the color
#A46BB5 is obtained.