The hex color #3fdd9c is a light color. The web-safe version is Hex
#33CC99. A complementary color is
#C02263. The grayscale version is
#939393. A 20% lighter version of the original color is
#72FFCF, and Hex
#0CAA69 is the 20% darker color. If the color is saturated by 10%, you get
#37E49D. If the color is desaturated by 10%, the color
#47D69B is obtained.