The images will appear and float on the screen for a certain period of time and then disappear again, the player's task is to distinguish what type of screen is on and quickly drag them into the classification frame image 2 by the screen before time runs out. * Each occurrence will randomize different images, different colors. * 2D display: each type collects all 3 images through the screen * Easy 3D display: each type collects enough 5 images to be displayed on screen * Medium 3D screen: each type collects enough 7 pictures to be displayed on screen * Difficult 3D display: each type collects enough 10 images through screen
