CSS3 水平垂直居中
Center the child elements of a div box by using the box-align and box-pack properties together:div{width:350px;height:100px;border:1px solid black;/* Internet Explorer 10 */display:-ms-flexbox;-ms-flex-pack:center;-ms-flex-align:center;/* Firefox */display:-moz-box;-moz-box-pack:center;-moz-box-align:center;/* Safari, Opera, and Chrome */display:-webkit-box;-webkit-box-pack:center;-webkit-box-align:center;/* W3C */display:box;box-pack:center;box-align:center;}

?From:http://www.w3schools.com/cssref/css3_pr_box-pack.asp