„subpages Extended“ as submenu in an individual sidebar

Hi, I recently purchases the Chicago-Pro theme. One question: I use the included widget „subpages Extended“ to have the submenu in an individual sidebar. This works. But all items are visible at once, means level 2 and level 3. Is there a way to open the level 3 items on klick on the menu-item on level 2 which contains the level 3 items? Example (this is what it looks like now): Chambers (level 1) — Reutlingen (level2) —— Directions (level 3) — Stuttgart (level2) —— Directions (level 3) When I click on the item „Chambers“ in the horizontal Main navigation, I would like to see the vertical sidebar navigation like this: — Reutlingen (level2) — Stuttgart (level2) When I click on „Stuttgart“, it should look like this: — Reutlingen (level2) — Stuttgart (level2) —— Directions (level 3) It should also look like this when I click on the menu item Chambers > Stuttgart > Directions in the horizontal flyout menu. Thank you very much in advance. Kind regards Alex