The hex color #3e66e5 is a dark color. The web-safe version is Hex
#3366CC. A complementary color is
#C1991A. The grayscale version is
#838383. A 20% lighter version of the original color is
#7199FF, and Hex
#0B33B2 is the 20% darker color. If the color is saturated by 10%, you get
#3763EF. If the color is desaturated by 10%, the color
#4569DB is obtained.