Edit in JSFiddle

div{
    color: #fff;
    text-align:center;
    padding:100px 0;
    width:400px;
    height:50px;
    background: linear-gradient(top, #3cf, #078);
    background: -webkit-linear-gradient(top, #3cf, #078);
    background: -moz-linear-gradient(top, #3cf, #078);
}

<div>CSS Gradient Background</div>