Retro Chengdu Cartoon Postcard

Create a vertical retro cartoon travel postcard for {argument name="city name" default="Chengdu"}. Use a bold vintage comic-book style with thick black outlines, bright pop-art colors, visible halftone dot texture, slightly grainy aged print, and playful exaggerated perspective. The sky is saturated cyan-blue with comic dots. At the very top, place huge arched yellow block letters reading {argument name="headline text" default="CHENGDU"}, with black shadow and outline; directly underneath add red Chinese characters {argument name="local city text" default="成都"} flanked by two red dots. In the upper right, add a red circular passport stamp that says “WELCOME TO CHENGDU” with a cute panda face and three wavy postal cancellation lines. The scene should show exactly 5 cream-and-peach puffy clouds: one large cloud on the upper left, one large cloud on the upper right, one partial cloud entering from the left middle edge, one small cloud left of center, and one small cloud right of center. Center the postcard around Chengdu landmarks: a tall TV tower rising from behind a giant faceted panda-head building, with a blue doorway at the panda’s mouth; make the panda head geometric and stone-like with black ears and eye patches. Along the lower skyline, include colorful simplified city buildings and green trees. On the left foreground, include a traditional Chinese pavilion with green tiled roofs, red lanterns, and a sign with Chinese characters. On the right foreground, include a yellow vertical sign with Chinese characters {argument name="landmark sign text" default="太古里"}. Across the bottom, draw a bright blue river with wavy white highlights and an arched cream stone bridge on the right. In the bottom left foreground, place a roadside sign reading “I ♥ CHENGDU” and a cute standing panda mascot waving beside it. Counted visible elements: 1 main headline, 1 Chinese subtitle, 1 red passport stamp, 5 clouds, 1 central TV tower, 1 giant panda-head building, 1 traditional pavilion, 1 vertical landmark sign, 1 river, 1 arched bridge, 1 “I love Chengdu” sign, and 1 waving panda mascot. Keep the composition busy but legible, like a cheerful tourist souvenir postcard, with no photorealism and no extra text beyond the specified lettering.