The hex color #a4def5 is a light color. The web-safe version is Hex
#99CCFF. A complementary color is
#5B210A. The grayscale version is
#D2D2D2. A 20% lighter version of the original color is
#D7FFFF, and Hex
#71ABC2 is the 20% darker color. If the color is saturated by 10%, you get
#9FDFF8. If the color is desaturated by 10%, the color
#A9DDF2 is obtained.