The hex color #687bb9 is a dark color. The web-safe version is Hex
#6666CC. A complementary color is
#978446. The grayscale version is
#898989. A 20% lighter version of the original color is
#9BAEEC, and Hex
#354886 is the 20% darker color. If the color is saturated by 10%, you get
#657ABE. If the color is desaturated by 10%, the color
#6B7CB4 is obtained.