【8】ie css hack

1. 

   "\9"   IE6/IE7/IE8/IE9/IE10都生效

   "\0"   IE8/IE9/IE10都生效，是IE8/9/10的hack

   "\9\0" 只对IE9/IE10生效，是IE9/10的hack

2.

@media \0screen {body { background: red; }}                      只对IE8有效
@media \0screen\,screen\9{body { background: blue; }}            只对IE6/7/8有效
@media screen\0 {body { background: green; }}                    只对IE8/9/10有效
@media screen and (min-width:0\0) {body { background: gray; }}   只对IE9/10有效