Subject: In the center of the frame is a 2.5D three-dimensional cloud service icon labeled "Cloud", below the cloud icon is a blue translucent server device, surrounded by IoT function icons of security protection, data statistics, document input, and smart energy. Scene: A minimalist tech-sense low-polygon geometric space, background and ground are both light off-white block geometric structures, no redundant decorations, highlighting the IoT tech-related elements in the middle. Style: 2.5D light pseudo-object tech illustration style, elements with round and concise lines, presenting a flat three-dimensional effect, meeting the standard design sense of commercial promotional posters. Color tone: Overall is a cool-toned tech color scheme, based on light off-white, main visuals use different levels of bright blue and dark blue, with a very small amount of bright yellow as functional accent colors, refreshing and clean visual effect, full of tech sense. Lighting: Overall adopts uniform and soft diffuse light, no strong light and shadow contrast, each 2.5D element has extremely faint soft shadows to highlight the three-dimensional effect, overall light is bright and transparent. Composition: Promotional poster composition, the middle is the core visual illustration area, with clear and easy-to-read information hierarchy. Purpose: Used for vertical formal promotional posters for World IoT Day popular science, IoT industry promotion, and related tech event promotion.