The hex color #51a7cd is a light color. The web-safe version is Hex
#6699CC. A complementary color is
#AE5832. The grayscale version is
#979797. A 20% lighter version of the original color is
#84DAFF, and Hex
#1E749A is the 20% darker color. If the color is saturated by 10%, you get
#4AA9D2. If the color is desaturated by 10%, the color
#58A5C8 is obtained.