<style>div>span{font-size:100px}</style> <div><p><span>11</span></p><span>11</span><span>21</span><s
<style> div > span{font-size:100px} </style><div > <p> <span>11</span> </p> <span>11</span> <span>21</span> <span>31</span> </div>效果如下
可以看出来>号代表div > span 只对子元素起作用对子孙元素不起作用
