Articles that feel good:

Deep understanding of negative margin values ​​in CSS
https://www.cnblogs.com/xiaohuochai/p/5314289.html
vlc video
https://www.cnblogs.com/whisperzzZ/articles/8692149.html
position: sticky
https:/ /www.zhangxinxu.com/wordpress/2018/12/css-position-sticky/
CSS tips
https://juejin.im/post/5da3a357f265da5b6723ee1e
flex layout
https://mp.weixin.qq.com/s/NnIL0SBsVLJI6lJDJMKewA

AndroidStudio gradle version issue
https://www.jianshu.com/p/f4b43fc3c33f