The hex color #3f29e0 is a dark color. The web-safe version is Hex
#3333CC. A complementary color is
#C0D61F. The grayscale version is
#6D6D6D. A 20% lighter version of the original color is
#725CFF, and Hex
#0C00AD is the 20% darker color. If the color is saturated by 10%, you get
#3A22EB. If the color is desaturated by 10%, the color
#4430D5 is obtained.