frappe/frappe/public/css/tree.css

.tree {
  padding: 15px;
}
.tree li {
  list-style: none;
  margin: 2px 0px;
}
ul.tree-children {
  padding-left: 20px;
}
.tree-link {
  cursor: pointer;
  display: inline-block;
  padding: 1px;
}
.tree-link.active i {
  color: #5e64ff !important;
}
.tree-hover {
  background-color: #F7FAFC;
  min-height: 20px;
  border: 1px solid #d1d8dd;
}
.tree-node-toolbar {
  display: inline-block;
  padding: 0px 5px;
  margin-left: 15px;
  margin-bottom: -4px;
  margin-top: -8px;
}
@media (max-width: 767px) {
  ul.tree-children {
    padding-left: 10px;
  }
}
.tree,
.tree-node {
  position: relative;
}
.tree.opened::before,
.tree-node.opened::before,
.tree:last-child::after,
.tree-node:last-child::after {
  content: '';
  position: absolute;
  top: 16px;
  left: 8px;
  height: calc(100% - 26px);
  width: 1px;
  background: #d1d8dd;
  z-index: -1;
}
.tree:last-child::after,
.tree-node:last-child::after {
  top: 11px;
  left: -13px;
  height: calc(100% - 15px);
  width: 3px;
  background: #fff;
}
.tree.opened > .tree-children > .tree-node > .tree-link::before,
.tree-node.opened > .tree-children > .tree-node > .tree-link::before {
  content: '';
  position: absolute;
  width: 15px;
  height: 1px;
  top: 10px;
  left: -11px;
  z-index: -1;
  background: #d1d8dd;
}
.tree.opened::before {
  left: 23px;
  top: 33px;
  height: calc(100% - 67px);
}
.tree-link.active ~ .balance-area {
  color: #36414C !important;
}