E::placeholder { sRules }

::placeholder的使用示例:

<input type="text" placeholder="占位符" />input::-webkit-input-placeholder {color: #999;}input:-ms-input-placeholder { // IE10+color: #999;}input:-moz-placeholder { // Firefox4-18color: #999;}input::-moz-placeholder { // Firefox19+color: #999;}

引用地址http://www.css88.com/book/css/selectors/pseudo-element/placeholder.htm