The hex color #28C9F0 is a light color. The web-safe version is Hex
#33CCFF. A complementary color is
#D7360F. The grayscale version is
#A0A0A0. A 20% lighter version of the original color is
#5BFCFF, and Hex
#0096BD is the 20% darker color. If the color is saturated by 10%, you get
#1CCDF8. If the color is desaturated by 10%, the color
#34C5E8 is obtained.