The hex color #684bcd is a dark color. The web-safe version is Hex
#6633CC. A complementary color is
#97B432. The grayscale version is
#808080. A 20% lighter version of the original color is
#9B7EFF, and Hex
#35189A is the 20% darker color. If the color is saturated by 10%, you get
#6646D5. If the color is desaturated by 10%, the color
#6A50C5 is obtained.