The hex color #1b3d6f is a dark color. The web-safe version is Hex
#333366. A complementary color is
#E4C290. The grayscale version is
#424242. A 20% lighter version of the original color is
#4E70A2, and Hex
#000A3C is the 20% darker color. If the color is saturated by 10%, you get
#173C73. If the color is desaturated by 10%, the color
#1F3E6B is obtained.