The hex color #b4e40b is a light color. The web-safe version is Hex
#CCCC00. A complementary color is
#4B1BF4. The grayscale version is
#8C8C8C. A 20% lighter version of the original color is
#E7FF3E, and Hex
#81B100 is the 20% darker color. If the color is saturated by 10%, you get
#B8ED00. If the color is desaturated by 10%, the color
#B0DB18 is obtained.