#toTop {
    background: transparent url('../images/top.png') no-repeat;
    background-position: center top;
    border: none;
    bottom: 50px;
    color: transparent;
    display: none;
    height: 40px;
    left: 50%;
    margin-left: 550px;
    overflow: hidden;
    position: fixed;
    text-decoration: none;
    text-indent: -9999px;
    -webkit-transition: all .7s ease;
    -moz-transition: all .7s ease;
    -ms-transition: all .7s ease;
    -o-transition: all .7s ease;
    transition: all .7s ease;
    width: 39px;
    z-index: 20;
}
#toTop:hover,
#toTop:focus {
    background-position: center bottom;
    outline: medium none;
}