Brain Fuell on Instagram: "The short video features a simple yet ingenious optical illusion: a hand holds a transparent plastic ruler horizontally across the screen while slowly sliding it to the right. On the ruler's edge, large black numbers from 0 to 10 are printed. As the ruler moves, these numbers cleverly align one by one with a roughly scribbled chibi-style face drawn in black marker on a white background below, transforming the neutral doodle into 11 distinct facial expressions over abou