The hex color #3f36a8 is a dark color. The web-safe version is Hex
#333399. A complementary color is
#C0C957. The grayscale version is
#5F5F5F. A 20% lighter version of the original color is
#7269DB, and Hex
#0C0375 is the 20% darker color. If the color is saturated by 10%, you get
#3C32AF. If the color is desaturated by 10%, the color
#423AA1 is obtained.