.collapsible {
  cursor: pointer;
  font-size: 1.5em;
}
.collapsible .icon {
  transform-origin: 50% 100% 0;
  width: 25px;
  margin: 0;
  padding: 0;
  height: 25px;
  float: right;
}
.collapsible:hover {
  opacity: 0.7;
}