Menu Item Settings > General
How to apply a custom class or ID to the link (anchor)
The WordPress menu system already provides an ID for each menu item and a way to add custom classes. However, if you have a specific need to add the class or ID to the anchor (<a>) rather than the list item (<li>), you can use these menu item settings.
Common usage
– Custom styling with precise targeting
– Support for third party scripts like lightboxes or Google Analytics.