I'm trying to develop a menu bar for a theme that, when the admin adds a category as a child on the menu, it displays the recent posts of that category. Example: I have a menu called "jobs" which has the submenu "industry" that displays the most recent posts (with thumbnails) on the right.
Resuming, I want to create a menu like Business Insider.
By now I have this code:
Category menu item and its last 10 posts as sub-menu
I don't understand how to add thumbnails to that code and, most importantly, I can't realize how to change the style of the menu via that code.