The hex color #3d28d0 is a dark color. The web-safe version is Hex
#3333CC. A complementary color is
#C2D72F. The grayscale version is
#676767. A 20% lighter version of the original color is
#705BFF, and Hex
#0A009D is the 20% darker color. If the color is saturated by 10%, you get
#3922DB. If the color is desaturated by 10%, the color
#412EC6 is obtained.