Dropdown menu (just pass on the phone)

I would like to resolve when you access the site https://aszsa.com.ar by phone.
Clicking on the menu displays all the submenu options
MENU
+ SUBMENU 1
-SUBMENU 1.1
-SUBMENU 1.2
– SUBMENU 1.2.1
– SUBMENU 1.2.2
+ SUBMENU 2
-SUBMENU 2.1
-SUBMENU 2.2
– SUBMENU 1.2.1
– SUBMENU 1.2.2

I would like the submenu to be displayed only and if we click on the submenu1 just there the submenu2 is displayed. It only happens on the phone or when it is shown as responsive.

MENU
(click on MENU)
Show ——————
MENU
+ SUBMENU 1
+ SUBMENU 2
(CLICK SUBMENU 1)
Show————-
MENU
-SUBMENU1
-SUBMENU 1.1
-SUBMENU 1.2

Etc etc

Thank You

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