.custom-tree /deep/ .ant-menu-item-group-title {
  position: relative;
}
.custom-tree /deep/ .ant-menu-item-group-title:hover .btn {
  display: block;
}
.custom-tree /deep/ .ant-menu-item:hover .btn {
  display: block;
}
.custom-tree /deep/ .btn {
  display: none;
  position: absolute;
  top: 0;
  right: 10px;
  width: 20px;
  height: 40px;
  line-height: 40px;
  z-index: 1050;
}
.custom-tree /deep/ .btn:hover {
  -webkit-transform: scale(1.2);
          transform: scale(1.2);
  -webkit-transition: 0.5s all;
  transition: 0.5s all;
}