The hex color #3f3ad0 is a dark color. The web-safe version is Hex
#3333CC. A complementary color is
#C0C52F. The grayscale version is
#6E6E6E. A 20% lighter version of the original color is
#726DFF, and Hex
#0C079D is the 20% darker color. If the color is saturated by 10%, you get
#3A35DA. If the color is desaturated by 10%, the color
#443FC6 is obtained.