EXTEND

.circle {
  width: 25px;
  height: 25px;
  border-radius: 50%;
  outline: none;
  border: 0;
  cursor: pointer;
}

.loggedIn {
  @extend .circle;
  display: inline-block;
  vertical-align: middle;
  background: #00FF00;
}

.unLogged {
  @extend .circle;
  background: red;
}