sketch style, 2D image, black line, clear lines, flat color, expressive linework, varied line weight, clean composition, A young man with medium-length brown hair and glasses. He is dressed in simple youth clothes. He is holding a birthday cake in his hands and has a happy expression. The inscription "40!" is written in the background., sketch style, 2D image, black line, clear lines, flat color, expressive linework, varied line weight, clean composition
