The hex color #31b99e is a light color. The web-safe version is Hex
#33CC99. A complementary color is
#CE4661. The grayscale version is
#838383. A 20% lighter version of the original color is
#64ECD1, and Hex
#00866B is the 20% darker color. If the color is saturated by 10%, you get
#29BEA1. If the color is desaturated by 10%, the color
#39B49B is obtained.