<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <meta http-equiv="X-UA-Compatible" content="IE=edge"> <meta name="viewport" content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0"> <title>rem设计</title> <script type="text/javascript"> document.querySelector('html').style.fontSize=window.screen.width / 20 +'px'; // 针对PC端的切换屏幕大小设置的 window.onresize=function(){ document.querySelector('html').style.fontSize=window.screen.width / 20 +'px'; } </script> <style> .content{ background-color: hotpink; width: 5rem; height: 5rem } </style> </head> <body> <div class="content"> </div> </body> </html>