The hex color #e4fe5f is a light color. The web-safe version is Hex
#CCFF66. A complementary color is
#1B01A0. The grayscale version is
#C0C0C0. A 20% lighter version of the original color is
#FFFF92, and Hex
#B1CB2C is the 20% darker color. If the color is saturated by 10%, you get
#E8FF55. If the color is desaturated by 10%, the color
#E0F869 is obtained.