Ключевые слова: activity, architecture, back, background, backgrounds, billboard, blue, building, business, cloud, construction, crane, dawn, day, development, dusk, engineer, engineering, equipment, exterior, frame, fuel, generation, industry, large, lit, machinery, metal, nature, night, occupation, outdoors, power, silhouette, site, sky, skyline, skyscraper, steel, structure, sun, sunlight, sunrise, sunset, technology, urban, working, yellow,