.glyphicon {
  position: relative;
  display: inline-block;
  width: 40px;
  height: 40px;
}
.glyphicon::before {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-family: 'Glyphicons Halflings';
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.glyphicon--home::before {
  content: '\e021';
}
.glyphicon--book::before {
  content: '\e043';
}
.glyphicon--profile::before {
  content: '\e019';
}
.glyphicon--user::before {
  content: '\e008';
}
.glyphicon--login::before {
  content: '\e161';
}
.glyphicon--logout::before {
  content: '\e163';
}