设置input 中placeholder的样式
::-webkit-input-placeholder { /* Chrome/Opera/Safari */ position: relative; top: 4px; } ::-moz-placeholder { /* Firefox 19+ */ position: relative; top: 4px; } :-ms-input-placeholder { /* IE 10+ */ position: relative; top: 4px; } :-moz-placeholder { /* Firefox 18- */ position: relative; top: 4px; }