           <button type="button" class="btn btn-danger">1</button>
                        <button type="button" class="btn btn-danger">2</button>

                        <div class="btn-group">
                          <button type="button" class="btn btn-danger dropdown-toggle dropdown-icon" data-toggle="dropdown">
                          </button>
                          <div class="dropdown-menu">
                            <a class="dropdown-item" href="#">Dropdown link</a>
                     