The hex color #4037AB is a dark color. The web-safe version is Hex
#333399. A complementary color is
#BFC854. The grayscale version is
#616161. A 20% lighter version of the original color is
#736ADE, and Hex
#0D0478 is the 20% darker color. If the color is saturated by 10%, you get
#3D33B2. If the color is desaturated by 10%, the color
#433BA4 is obtained.