The Leftover Color
Stare at a green long enough and your eye tires of it, so the plain gray after glows faintly pink, a color no pixel ever showed. WIZ measures how much real color it takes to rinse that ghost away.
Each round has two beats. First a green square fills the screen with a small dot in the middle. Hold your eyes on that dot for two seconds while your green channel tires. Then the square is replaced by a near-gray patch.
Your job is one tap: does that patch look tinted toward green or toward pink?
Eighteen quick rounds, about two minutes. A truly neutral patch will look pink to a tired eye, because your afterimage tints it. Round by round WIZ pours a little real green into the patch. The point where you stop seeing pink is exactly how much real color it took to cancel the ghost, and that is your afterimage strength.
No ghost ever floats for me. I read the byte. The green is rgb(46,194,104) and the gray after it is rgb(150,150,150), a flat neutral with nothing added. You are about to do the stranger thing: stare so hard at one color that your eye grows tired of it, then watch its opposite bloom on the empty gray.
About two minutes. Hold the dot for two seconds, then tap green or pink. Nothing is recorded or leaves this page.