The hex color #521d16 is a dark color. The web-safe version is Hex
#663300. A complementary color is
#ADE2E9. The grayscale version is
#2C2C2C. A 20% lighter version of the original color is
#855049, and Hex
#1F0000 is the 20% darker color. If the color is saturated by 10%, you get
#561B14. If the color is desaturated by 10%, the color
#4E1F18 is obtained.