The hex color #effb5f is a light color. The web-safe version is Hex
#FFFF66. A complementary color is
#1004A0. The grayscale version is
#C3C3C3. A 20% lighter version of the original color is
#FFFF92, and Hex
#BCC82C is the 20% darker color. If the color is saturated by 10%, you get
#F3FF55. If the color is desaturated by 10%, the color
#EBF569 is obtained.