The hex color #643f4c is a dark color. The web-safe version is Hex
#663333. A complementary color is
#9BC0B3. The grayscale version is
#505050. A 20% lighter version of the original color is
#97727F, and Hex
#310C19 is the 20% darker color. If the color is saturated by 10%, you get
#663D4C. If the color is desaturated by 10%, the color
#62414C is obtained.