耐候钢顶棚：锈面薄板与细长支柱

Design an urban canopy in weathering steel, built so the material's ageing is the whole aesthetic. Show a folded steel plate roof, its plate only twelve millimetres thick, stiffened by shallow upstands along its edges so no beams are needed, carried on slim steel posts of the same alloy set at wide intervals. Detail the surface as a deep even orange-brown patina, matte and slightly granular, its tone varying subtly across the plate where rain has run — darker streaks below each fold, paler where the surface stays dry. Show every joint as a plainly visible bolted lap with the bolt heads rusted to match, and the plate edges left raw and square so the material's thinness reads at every boundary. Detail the paving directly below as pale concrete faintly stained where runoff has marked it over the years, recording the roof's outline on the ground. Show the contrast between the rust-orange steel and the surrounding green as the image's colour idea. Set it in a park plaza with mown grass, gravel paths and mature trees. Show soft overcast light so the patina reads richly. Photorealistic, weathered, rust orange against green, eye-level three-quarter view.