A mature bearded man, 40yo, wearing black-framed glasses, white shirt, dark blue jeans, brown leather belt, standing in a modern office, near a whiteboard filled with diagrams and notes, holding a marker, explaining software architecture design to a group of young engineers, seated around a wooden table, surrounded by computers, laptops, and empty coffee cups, with a cityscape view from the window, soft natural light, warm atmosphere, shallow depth of field, realistic style.