背景图片 由远及近 由近及远

.square-header {

width: 100%;

height: 470px;

margin-top: -77px;

font-size: 44px;

line-height: 540px;

color: #fff;

background: url(http://mat1.gtimg.com/v/coral_yp_2015_v3.0/square/images/header.jpg) center top no-repeat #190102;

animation: starbigger 20s infinite ease;

}