Twitter HQ building, modern architecture, glass facade, steel frame, rooftop garden, cityscape background, San Francisco, sunny day, blue sky, few white clouds, birds flying, people walking outside, large windows, open office space, minimalist interior design, wooden tables, ergonomic chairs, laptops and desktops, scattered papers and notes, coffee cups, water bottles, collaborative workspace, natural light pouring in, soft shadows, 3/4 composition, shallow depth of field, bright and airy atmosphere.