The hex color #647b6c is a dark color. The web-safe version is Hex
#666666. A complementary color is
#9B8493. The grayscale version is
#6E6E6E. A 20% lighter version of the original color is
#97AE9F, and Hex
#314839 is the 20% darker color. If the color is saturated by 10%, you get
#637C6C. If the color is desaturated by 10%, the color
#657A6C is obtained.