Carte postale en line art

Create an editorial travel postcard illustration of the city or destination described in the user request, drawn entirely in black felt-tip marker line art on a clean white background. Sketch the place's most iconic architecture, landmarks, local transport, food, plants, and cultural objects as simple contour drawings with slightly wobbly hand-drawn lines, natural line-weight variation, open line endings, and small charming imperfections that feel genuinely handmade rather than vector-perfect. Keep every shape flat and simplified with minimal interior detail — no fills, gradients, heavy shadows, or color noise. Arrange the elements into a balanced postcard composition with generous white space so the page feels open, light, and effortless, and work the destination's name into the layout as casual hand-lettered postcard type. If the user names a single accent color, apply it sparingly to a few selected details such as sky, water, windows, or signage, and never introduce any other color; otherwise stay purely black and white. The mood is warm, playful, and quietly elegant, like a designer's travel sketchbook page. No photorealism, no 3D rendering, no watermark. User request: Shanghai with sky-blue accents