简约风蓝色渐变星形应用图标标志设计

Flat gradient app icon, 4-pointed sparkle star shape, diagonal orientation (tips pointing top-left, top-right, bottom-left, bottom-right), smooth blue-to-cyan linear gradient fill, no 3D effect, no glass texture, minimal flat design, solid color with smooth gradient transition, clean vector look, rounded plump body, on solid black rounded square background, centered composition