The hex color #3f90a6 is a dark color. The web-safe version is Hex
#339999. A complementary color is
#C06F59. The grayscale version is
#7C7C7C. A 20% lighter version of the original color is
#72C3D9, and Hex
#0C5D73 is the 20% darker color. If the color is saturated by 10%, you get
#3992AA. If the color is desaturated by 10%, the color
#458EA2 is obtained.