.dstreeview {
  list-style: none;
  padding-left: 20px;
}
.dstreeview li {
  position: relative;
  padding: 5px 0 5px 20px;
}
.dstreeview .tree-toggle {
  position: absolute;
  left: 0;
  cursor: pointer;
}
.dstreeview li.has-child > .tree-toggle:before {
  content: "+";
}
.dstreeview li.expanded > .tree-toggle:before {
  content: "-";
}