Anchor Tags Highlighting and Underlining (from https://fontforge.github.io/en-US/downloads/mac/)

anchor-highlighting.css

/* box-shadow underline */
.content a:not(.btn) {
  box-shadow: inset 0 -5px 0 #ff772f;
  color: inherit;
  padding: 0 2px;
  margin: 0 -2px;
  display: inline-block;
}

/* hightlight on hover */
a:not(.btn):not(.brand):hover,
.breadcrumbs .doc-search-form .btn:hover {
  color: white;
  background: #ff772f;
}