.hpb-trigger {
   position: relative;
}
 
.hpb-trigger:after {
  content: "";
  position: absolute;
  top: 8px;
  left: 4px;
  width: 0;
  height: 0;
  border: 8px solid transparent;
  border-top-color: #84b4ec;
}
 
.hpb-trigger.ac:after {
  content: "";
  position: absolute;
  top: 0px;
  left: 4px;
  width: 0;
  height: 0;
  border: 8px solid transparent;
  border-top-color: #84b4ec;
  transform: rotate(180deg);
}