The hex color #516c5c is a dark color. The web-safe version is Hex
#666666. A complementary color is
#AE93A3. The grayscale version is
#5E5E5E. A 20% lighter version of the original color is
#849F8F, and Hex
#1E3929 is the 20% darker color. If the color is saturated by 10%, you get
#506D5C. If the color is desaturated by 10%, the color
#526B5C is obtained.