The hex color #3d3e99 is a dark color. The web-safe version is Hex
#333399. A complementary color is
#C2C166. The grayscale version is
#5C5C5C. A 20% lighter version of the original color is
#7071CC, and Hex
#0A0B66 is the 20% darker color. If the color is saturated by 10%, you get
#3A3B9F. If the color is desaturated by 10%, the color
#404193 is obtained.