竖版像素风太空射击游戏背景

Create a vertical retro pixel-art space shooter scrolling background, designed as a seamless mobile game asset. The canvas is a tall 9:16 portrait frame with a dark central flight corridor left mostly open for gameplay. Fill the scene with a deep black starfield, hundreds of tiny white, blue, and violet pixel stars, and two luminous vertical nebula streams: one winding down the left side in electric purple and blue, and one winding down the right side in purple with cyan highlights. Add exactly 3 visible planets: a large purple cratered planet near the upper left edge, a large blue-purple rim-lit planet partially cropped on the lower right edge, and a small purple moon just below that lower-right planet. Add exactly 22 rocky asteroids of varied sizes, irregular cratered gray-brown forms with purple shadowing, distributed around the border while keeping the center mostly clear: 1 huge asteroid near the upper right, 1 medium asteroid at the right-middle edge, 1 medium asteroid at the lower left edge, 1 large asteroid cropped at the bottom left corner, 1 large asteroid cropped at the lower right corner, plus 17 smaller asteroids scattered near the top edge, side edges, and lower border. Use crisp pixel-art rendering with high-detail dithering, chunky jagged silhouettes, bright rim highlights, no outlines that look vector-smooth, no ships, no UI, no text, no watermark. Color palette: black space, violet and magenta nebula clouds, electric blue accents, white star glints, gray rocky asteroids with cool purple shadows. The image should feel production-ready as a vertical shoot ’em up background tile, dramatic but readable, with the gameplay lane clear in the center.

创作一张竖版复古像素风太空射击游戏滚动背景，设计为无缝衔接的移动端游戏素材。画布采用 9:16 的高比例竖屏框架，深色的中央飞行通道保持大部分留白，以供游戏操作。场景填充深邃的黑色星空，点缀数百颗细小的白色、蓝色和紫色像素星点，以及两条发光的垂直星云流：左侧是一条蜿蜒而下的电光紫蓝色星云，右侧是一条带有青色高光的紫色星云。添加 3 颗清晰可见的行星：左上方边缘有一颗巨大的紫色陨石坑行星，右下方边缘有一颗被部分裁剪的蓝紫色轮廓光行星，以及在那颗右下行星下方的一颗小型紫色卫星。添加 22 颗大小不一的岩石小行星，形状为带有紫色阴影的不规则灰褐色坑洼状，分布在边界周围，同时保持中心区域开阔：右上角附近 1 颗巨大陨石，右侧中部边缘 1 颗中型陨石，左下边缘 1 颗中型陨石，左下角 1 颗被裁剪的大型陨石，右下角 1 颗被裁剪的大型陨石，其余 17 颗较小陨石散布在顶部边缘、侧边和底部边界。采用清晰的像素艺术渲染，具备高细节的抖动效果、厚实的锯齿轮廓、明亮的边缘高光，无矢量平滑轮廓，无飞船，无 UI，无文字，无水印。调色板：黑色太空、紫红色星云云团、电光蓝点缀、白色星光闪烁、带有冷紫色阴影的灰色岩石小行星。图像应呈现出可直接用于生产的竖版飞行射击游戏背景图效果，既具戏剧性又具备良好的可读性，确保中心游戏通道清晰。