twbs--bootstrap/docs/assets/scss/_anchor.scss

//
// Store the link icon as a base64 embedded icon font.
//
@font-face {
  font-family: 'anchorjs-icons';
  src: url(data:application/x-font-ttf;charset=utf-8;base64,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) format('truetype'),
  url(data:application/font-woff;charset=utf-8;base64,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) format('woff');
  font-style: normal;
  font-weight: normal;
}

.anchorjs-icon {
  font-family: 'anchorjs-icons';
  font-style: normal;
  font-variant: normal;
  font-weight: normal;
  line-height: 1;
  speak: none;
  text-transform: none;

  // Better Icon Rendering
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

//
// Link placement and hover behavior.
//
.anchorjs-link {
  opacity: 0;
  text-decoration: none;
}
*:hover > .anchorjs-link,
.anchorjs-link:focus  {
  // To fade links as they appear, change transition-property from 'color' to 'all'
  opacity: 1;
  transition: color .16s linear;
}

//
// Make screen-reader friendly description text visually hidden.
//
.anchorjs-description {
  border: 0;
  clip: rect(0 0 0 0);
  height: 1px;
  margin: -1px;
  overflow: hidden;
  padding: 0;
  position: absolute;
  width: 1px;
}

//
// Reasonable default styles.
// Feel free to override or replace these with your own.
//
// .anchorjs-link:link    { color: #DFD487; }
// .anchorjs-link:visited { color: #DFD487; }
// .anchorjs-link:hover   { color: #EC7963; }
// .anchorjs-link:active  { color: #EC7963; }

.anchorjs-link {
  float: left;
  width: 1.2em;
  height: 1em;
  padding-right: .2em;
  margin-top: .25em;
  margin-left: -1.2em;
  font-size: 70%;
  color: inherit;
  text-align: center;
}
*:hover > .anchorjs-link:hover {
  color: $brand-primary;
  text-decoration: none;
}

// .anchorjs-icon {
//   font-size: 90%;
//   padding-left: 6px;
// }

.anchorjs-icon:before {
  content: '\e600';
  // alternative icons -- uncomment to use
  //
  // content: '#';
  // content: '¶';
  // content: '❡';
  // content: '§';
}

@include media-breakpoint-down(sm) {
  .anchorjs-link {
    display: none;
  }
}