The hex color #237DF3 is a dark color. The web-safe version is Hex
#3366FF. A complementary color is
#DC820C. The grayscale version is
#868686. A 20% lighter version of the original color is
#56B0FF, and Hex
#004AC0 is the 20% darker color. If the color is saturated by 10%, you get
#197CFE. If the color is desaturated by 10%, the color
#2D7EE8 is obtained.