The hex color #3f58d2 is a dark color. The web-safe version is Hex
#3366CC. A complementary color is
#C0A72D. The grayscale version is
#787878. A 20% lighter version of the original color is
#728BFF, and Hex
#0C259F is the 20% darker color. If the color is saturated by 10%, you get
#3955DB. If the color is desaturated by 10%, the color
#455BC9 is obtained.