Sue, here is a demo file:
MegaMenu.xar.
There is nothing rocket science or complex in the design, or pretty for that matter.
If you are on any site page and click More.., you are taken to the mega menu.
The More.. is replaced with the Back Link.
I included your Anchors on the Home page as well as a Top of Page as I made the top menu bar Sticky.
No sub-menus, just a page of mess to play with.
Acorn
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