The hex color #3f75a8 is a dark color. The web-safe version is Hex
#336699. A complementary color is
#C08A57. The grayscale version is
#747474. A 20% lighter version of the original color is
#72A8DB, and Hex
#0C4275 is the 20% darker color. If the color is saturated by 10%, you get
#3A75AD. If the color is desaturated by 10%, the color
#4475A3 is obtained.