.tree-view {
    list-style-type: none;
  }
  
  .tree-view {
    margin: 0;
    padding: 0;
  }
  
  .tree-view-caret {
    cursor: pointer;
    -webkit-user-select: none;
    /* Safari 3.1+ */
    -moz-user-select: none;
    /* Firefox 2+ */
    -ms-user-select: none;
    /* IE 10+ */
    user-select: none;
  }
  
  .tree-view-caret::before {
    content: "+";
    color: black;
    display: inline-block;
    margin-right: 6px;
  }
  
  .tree-view-expanded-caret::before {
    content: "-";
    color: dodgerblue;
  }
  
  .tree-view-nested {
    display: none;
    list-style-type: none;
  }
  
  .tree-view-active {
    display: block;
  }