题解 | #CSS单位（一）#
CSS单位（一）
https://www.nowcoder.com/practice/8e6cdbc7ad5b4f2b840d5aad314506b1
{"html":"<!DOCTYPE html>\n<html>\n\n<head>\n <meta charset=\"UTF-8\">\n <style>\n .box {\n /*补全代码*/\n width:4em;\n height:4em;\n \n}\n </style>\n</head>\n\n<body>\n <div class='box'></div> \n <script type=\"text/javascript\">\n /* 填写JavaScript */\n \n </script>\n</body>\n\n</html>","css":"","js":""}
em是相对于自身字体大小的单位
