The hex color #51fbcc is a light color. The web-safe version is Hex
#66FFCC. A complementary color is
#AE0433. The grayscale version is
#B3B3B3. A 20% lighter version of the original color is
#84FFFF, and Hex
#1EC899 is the 20% darker color. If the color is saturated by 10%, you get
#47FFCF. If the color is desaturated by 10%, the color
#5BF4C9 is obtained.