The hex color #81123c is a dark color. The web-safe version is Hex
#990033. A complementary color is
#7EEDC3. The grayscale version is
#454545. A 20% lighter version of the original color is
#B4456F, and Hex
#4E0009 is the 20% darker color. If the color is saturated by 10%, you get
#870D3B. If the color is desaturated by 10%, the color
#7B173D is obtained.