The hex color #a7191f is a dark color. The web-safe version is Hex
#990033. A complementary color is
#58E6E0. The grayscale version is
#4A4A4A. A 20% lighter version of the original color is
#DA4C52, and Hex
#740000 is the 20% darker color. If the color is saturated by 10%, you get
#B0141B. If the color is desaturated by 10%, the color
#9E1E23 is obtained.