yzhanweather (npm): Pure CSS animation for sakura, rain, snow, firefly and butterfly effects, high performance without affecting SEO. 纯 CSS 动画实现樱花、雨、雪、萤火虫和蝴蝶飞舞背景效果，高性能且不影响 SEO
Keywords: sakura|rain|snow|firefly|butterfly|pure|css|js|library|performance|SEO