The hex color #4fc9cd is a light color. The web-safe version is Hex
#66CCCC. A complementary color is
#B03632. The grayscale version is
#A2A2A2. A 20% lighter version of the original color is
#82FCFF, and Hex
#1C969A is the 20% darker color. If the color is saturated by 10%, you get
#47CDD1. If the color is desaturated by 10%, the color
#57C5C9 is obtained.