@media (min-width: 650px) {
.el-dialog {
    width: 500px;
}
.el-tree {
    margin-right: 20px;
    height: 400px;
    overflow: auto;
}
}
@media (max-width: 650px) {
.el-dialog {
    width: 100%;
    height: 100%;
    margin-top: 0 !important;
    z-index: 3;
}
}