I am thinking to create a vertical menu, which may contain sigle level or even multiple levels of submenus.
While mouse is hover one main menu item (parent menu), the related submenu items will appear one by one on the right hand side.
While click on one of the submenu item, the related page is loaded, and the menu and submenu will be remained and highlighted.
The Main menu contains 4 items, A, B, C and D
When mouse is hover Item C, the related submenu items, C.1, C.2 and C.3 will appear on the right
When click on one of the sunmenu items, such as Item C.3, the related page is loaded, and the menu and submenu will be remained and highlighted (with '<' shown below).
Item A Item B Item C< - Item C.1 Item D Item C.2 Item C.3<
Thank you so much!