.st-tree-table {
  .st-tree-table__icon {
    display: inline-block;
    width: 1.5em;
    line-height: 1.5em;
    margin: 0.1em;
    background-color: #eee;
    text-align: center;
    text-decoration: none;
    cursor: pointer;
  }
  :not(.st-tree-table__node--closed) .st-tree-table__icon:after {
    content: '-';
  }
  .st-tree-table__node--closed .st-tree-table__icon:after {
    content: '+';
  }
  .st-tree-table__node--leaf .st-tree-table__icon {
    visibility: hidden;
  }
  .st-tree-table__node--hidden {
    display: none;
  }
}