主题海报版式设计

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Flat illustration, high-end oriental fantasy style city poster design, vertical 9:16 composition. The layout uses a diagonal + S-shaped flow extending from the bottom left to top right. The background is deep black grading down to intense dark red, creating strong warm-cool contrast and spatial depth with faint stardust and grain texture. In the center, a flowing golden energy line winds through like a flame, extending upward from the base, featuring fluid texture, particle effects, and gradient highlights, with subtle energy debris and volumetric light.