quiet urban square with a billboard on a sleek transit hub, featuring glass buildings and reflective windows under a

billboard mockup city urban area densely populated panoramic cityscape modern rooftop historical buildings crowded streets people sky clear lighting visible distance environment vibrant bustling mix architecture dynamic signage advertising high definition scene visibility life living transit hub square glass reflective windows overcast light calm cool empty sleek structure open space quiet atmosphere design muted reflections deserted frame minimalistic smooth contemporary reflection steel urbanism polished tranquil backdrop commercial scenery vacant clean framework ai generated