The hex color #3f871c is a dark color. The web-safe version is Hex
#339933. A complementary color is
#C078E3. The grayscale version is
#4B4B4B. A 20% lighter version of the original color is
#72BA4F, and Hex
#0C5400 is the 20% darker color. If the color is saturated by 10%, you get
#3E8D17. If the color is desaturated by 10%, the color
#408121 is obtained.