链接：https://blog.csdn.net/phoooob/article/details/51565483
.custom-tree-node {
overflow: hidden;
flex: 1;
display: flex;
align-items: center;
justify-content: space-between;
font-size: 14px;
padding-right: 8px;
.el-icon-more {
display: none; //一开始不显示
}
&:hover {
.el-icon-more { //父级hover后再显示
display: inline;
}
}
}