Style submenu to open on mobile tap, not just arrow

Hi, right now, I can only open the submenus by tapping the arrow on mobile. I am looking to style my submenu items to open on a tap of the parent menu item, not just by tapping the arrow. I do not want to use a plugin. I am also not looking to set a link to the parent navigation item since not all parent navigation items have a parent page (such as “UV-C Basics”). I was reading some information saying that entering # in my parent item’s link field would set it to open the submenu, but that doesn’t work for me… maybe that was for a different situation. I found several related threads that didn’t answer my question. Not sure how developer-heavy this will be, or if it is something solved in the WordPress editor.

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