.short-video_teach{position:absolute;z-index:102;width:100%;height:100%}.short-video_teach_mask{position:absolute;width:100%;height:100%;background-color:#000;opacity:.5}.short-video_teach_image{position:absolute;left:20.5333333333vw;bottom:32vw;width:58.6666666667vw;height:26.6666666667vw}.short-video_teach_image img{width:100%}