I am not sure if this menu is of any real use, but it does demonstrate the use of 'flexbox' layout for menus and the animation of the 'order' style.

At the moment the 'order' animation is only supported by Firefox, so if you are using this browser and you click the '6. Garden' tab you will see it animate to the top of the list and tehn the submenu will slide down.

You can then click the same top level item to close the sub menu and return the top level to its original position in the list, or you can click another top level item to close the current open sub menu and return the current top level to its origianl position and then move the selected item to the top of the list and open its sub menu.