The hex color #3f12c7 is a dark color. The web-safe version is Hex
#3300CC. A complementary color is
#C0ED38. The grayscale version is
#5D5D5D. A 20% lighter version of the original color is
#7245FA, and Hex
#0C0094 is the 20% darker color. If the color is saturated by 10%, you get
#3C0AD2. If the color is desaturated by 10%, the color
#421ABC is obtained.