The hex color #312c7c is a dark color. The web-safe version is Hex
#333366. A complementary color is
#CED383. The grayscale version is
#484848. A 20% lighter version of the original color is
#645FAF, and Hex
#000049 is the 20% darker color. If the color is saturated by 10%, you get
#2F2981. If the color is desaturated by 10%, the color
#332F77 is obtained.