Perhaps I am missing it or need an additional bric for this functionality, but is there a way to show a secondary menu or additional pages when you hover or click on a link in the primary? Using Apple’s website, for example… when you click on Mac, it asks you what kind of Mac you want to learn more about.
For the record, I am not using WordPress for this project.
As you see on the apple website, those secondary menus are specific to the page not global.
You can of course create hidden elements that are shown on click too. Many ways to build things like this, depends on the design and content to how you would approach it. And if you wanted all those different secondary menus available globally.