Add a close button

/* css close icon addition */
.prettydropdown.arrow > ul.active > li.selected:before, 
.prettydropdown.arrow > ul.active > li.selected:after {
  position: absolute;
  top: 0px;
  right: 16px;  
  width: 16px;
  height: 16px;
  opacity: 1;  
  content: ' '; 
  width: 2px;  
}

.prettydropdown.arrow > ul.active > li.selected:before {
  transform: rotate(45deg);
}

.prettydropdown.arrow > ul.active > li.selected:after {
  transform: rotate(-45deg);
}

.prettydropdown.arrow > ul.active > li.selected:before, 
.prettydropdown.arrow > ul.active > li.selected:after,
.prettydropdown.arrow > ul.active > li.selected.hover:before, 
.prettydropdown.arrow > ul.active > li.selected.hover:after {  
  background-color: #fff;
}

.prettydropdown.arrow > ul.active > li.selected.nohover:before, 
.prettydropdown.arrow > ul.active > li.selected.nohover:after {  
  background-color: #777;
}

Submitted by OLSA.