.header{
    background: url(../images/banner.png);
    background-position: center;
    background-size: cover;
}
.u-1{
    height: 307px;
    background: url(../images/unique-1.png);
    background-size: cover;
    position: relative;
}
.u-2{
    height: 307px;
    background: url(../images/unique-2.png);
    background-size: cover;
    position: relative;
}
.u-3{
    height: 307px;
    background: url(../images/unique-3.png);
    background-size: cover;
    position: relative;
}