The hex color #51a177 is a light color. The web-safe version is Hex
#669966. A complementary color is
#AE5E88. The grayscale version is
#787878. A 20% lighter version of the original color is
#84D4AA, and Hex
#1E6E44 is the 20% darker color. If the color is saturated by 10%, you get
#4DA577. If the color is desaturated by 10%, the color
#559D77 is obtained.