The hex color #e73f3f is a dark color. The web-safe version is Hex
#FF3333. A complementary color is
#18C0C0. The grayscale version is
#777777. A 20% lighter version of the original color is
#FF7272, and Hex
#B40C0C is the 20% darker color. If the color is saturated by 10%, you get
#F23939. If the color is desaturated by 10%, the color
#DC4545 is obtained.