#backtotop {
    display: block;
    left: 1em;
    position: relative;
}
#backtotop a:hover img
{
    opacity: 1.0;
}
#backtotop a img
{
    opacity: 0.7;
}
#button-wraper 
{
    position: fixed;
    bottom: 0.5em;    
}
#backtotopcontainer {
    float: right; 
}