.svg-anchor {
    float: left;
    padding-right: 4px;
    margin-left: -20px;
    line-height: 1;

    opacity: 0;
    /*
    -webkit-transition: opacity 0.2s ease-in-out 0.1s;
    -moz-transition: opacity 0.2s ease-in-out 0.1s;
    -ms-transition: opacity 0.2s ease-in-out 0.1s;
    */
}

h2:hover .svg-anchor,
h3:hover .svg-anchor,
h4:hover .svg-anchor,
h5:hover .svg-anchor,
h6:hover .svg-anchor {
  opacity: 1;
}