ant-design-vue/components/vc-tree/demo/contextmenu.less

@contextmenuPrefixCls: rc-tree-contextmenu;
.@{contextmenuPrefixCls} {
  position: absolute;
  left: -9999px;
  top: -9999px;
  z-index: 1070;
  display: block;
  background-color: #fff;

  &-hidden {
    display: none;
  }

  &-inner {
    border: 1px solid #ddd;
    padding: 10px 20px;
  }
}