css pseudo classes

http://www.runoob.com/css/css-pseudo-classes.html

https://github.com/DataTables/Select/blob/master/css/select.dataTables.scss

https://cdn.datatables.net/select/1.2.7/css/select.dataTables.css

这个开源项目里面使用before和after生成checkbox的外观

css pseudo classes

原文地址：https://www.cnblogs.com/chucklu/p/9296004.html