.header-link:after {
  position: relative;
  left: 0.5em;
  opacity: 0;
  font-size: 0.8em;
  -moz-transition: opacity 0.2s ease-in-out 0.1s;
  -ms-transition: opacity 0.2s ease-in-out 0.1s;
}
h2:hover .header-link,
h3:hover .header-link,
h4:hover .header-link,
h5:hover .header-link,
h6:hover .header-link {
  opacity: 1;
}