https://www.ptt.cc/bbs/sex/M.1428913469.A.F77.html
https://www.zhihu.com/question/33757121
html,body{margin:0;height:100%;} body{ background: url(http://117.25.143.25/2018s.jpg) no-repeat center/cover; height: 100%; background-attachment: fixed;}
https://www.ptt.cc/bbs/sex/M.1428913469.A.F77.html
https://www.zhihu.com/question/33757121
html,body{margin:0;height:100%;} body{ background: url(http://117.25.143.25/2018s.jpg) no-repeat center/cover; height: 100%; background-attachment: fixed;}