.menuitem-container {
    position: relative;
}
.menuitem-container .menuitem-tree {
    position: absolute;
    border-top: 1px solid #f2f2f2;
    width: 334px;
    overflow: auto;
}
.menuitem-tree {
    padding-left: 10px;
}
.menuitem-tree-form-type {
    margin-left: -10px;
}
.menuitem-data {
    margin-left: 334px;
    border-left: 1px solid #f2f2f2;
}