The hex color #51969c is a light color. The web-safe version is Hex
#669999. A complementary color is
#AE6963. The grayscale version is
#818181. A 20% lighter version of the original color is
#84C9CF, and Hex
#1E6369 is the 20% darker color. If the color is saturated by 10%, you get
#4C989F. If the color is desaturated by 10%, the color
#569499 is obtained.