The hex color #c23a1b is a dark color. The web-safe version is Hex
#CC3333. A complementary color is
#3DC5E4. The grayscale version is
#5D5D5D. A 20% lighter version of the original color is
#F56D4E, and Hex
#8F0700 is the 20% darker color. If the color is saturated by 10%, you get
#CC3714. If the color is desaturated by 10%, the color
#B83E22 is obtained.