The hex color #a66dd2 is a light color. The web-safe version is Hex
#9966CC. A complementary color is
#59922D. The grayscale version is
#A2A2A2. A 20% lighter version of the original color is
#D9A0FF, and Hex
#733A9F is the 20% darker color. If the color is saturated by 10%, you get
#A668D7. If the color is desaturated by 10%, the color
#A672CD is obtained.