The hex color #1d2f3d is a dark color. The web-safe version is Hex
#333333. A complementary color is
#E2D0C2. The grayscale version is
#2E2E2E. A 20% lighter version of the original color is
#506270, and Hex
#00000A is the 20% darker color. If the color is saturated by 10%, you get
#1B2F3F. If the color is desaturated by 10%, the color
#1F2F3B is obtained.