The hex color #51e90c is a light color. The web-safe version is Hex
#66FF00. A complementary color is
#AE16F3. The grayscale version is
#6D6D6D. A 20% lighter version of the original color is
#84FF3F, and Hex
#1EB600 is the 20% darker color. If the color is saturated by 10%, you get
#4EF502. If the color is desaturated by 10%, the color
#54DD16 is obtained.