The hex color #31369c is a dark color. The web-safe version is Hex
#333399. A complementary color is
#CEC963. The grayscale version is
#565656. A 20% lighter version of the original color is
#6469CF, and Hex
#000369 is the 20% darker color. If the color is saturated by 10%, you get
#2D33A3. If the color is desaturated by 10%, the color
#353995 is obtained.