The hex color #42f9e7 is a light color. The web-safe version is Hex
#33FFFF. A complementary color is
#BD0618. The grayscale version is
#B6B6B6. A 20% lighter version of the original color is
#75FFFF, and Hex
#0FC6B4 is the 20% darker color. If the color is saturated by 10%, you get
#36FFEC. If the color is desaturated by 10%, the color
#4EF2E2 is obtained.