The hex color #cf301d is a dark color. The web-safe version is Hex
#CC3333. A complementary color is
#30CFE2. The grayscale version is
#5F5F5F. A 20% lighter version of the original color is
#FF6350, and Hex
#9C0000 is the 20% darker color. If the color is saturated by 10%, you get
#DA2B16. If the color is desaturated by 10%, the color
#C43524 is obtained.