The hex color #2d3f3c is a dark color. The web-safe version is Hex
#333333. A complementary color is
#D2C0C3. The grayscale version is
#383838. A 20% lighter version of the original color is
#60726F, and Hex
#000C09 is the 20% darker color. If the color is saturated by 10%, you get
#2C403C. If the color is desaturated by 10%, the color
#2E3E3C is obtained.