#side-dock {

    display:block;

    list-style:none;

    margin: 0 0 0 0;

    width: 60px;

    position: fixed; /*←➀*/

    bottom: 20px; /*←➁-1*/

    right: 8px;  /*←➁-2*/

    z-index: 99998; /*←➂*/

    opacity: 0.8; /*←➃*/   

    text-decoration: none;

    overflow: hidden;   

}  

#side-dock li {

    padding: 0 0 10px 0;

}  

   

#side-dock li a img:hover {

    margin: 0 0 0px -60px; /*←➄*/

}