The hex color #d91d0c is a dark color. The web-safe version is Hex
#CC3300. A complementary color is
#26E2F3. The grayscale version is
#565656. A 20% lighter version of the original color is
#FF503F, and Hex
#A60000 is the 20% darker color. If the color is saturated by 10%, you get
#E61705. If the color is desaturated by 10%, the color
#CC2313 is obtained.