This is a complex block top menu module and PrestaShop core modification service. An effect of the service is a possibility to create block top menu module with icons that will appear for main menu items.
With this modification of PrestaShop horizontal block top menu module and PrestaShop core you will have possibility to change the design of your block top menu module. Module will create a horizontal menu with icons for main items. You can decide what icon module will show.
Block top menu module modification
Modification of the module does not change the way of how module configuration works. Modification is only for design purposes and I change the main module .php file too. I can personalize the module colors and layout. Modification changes the way of how subcategories are visible in the menu (you can see it on the screenshot).
PrestaShop core modification
Core modifications gives you possibility to define icon for each page type that you can insert into the menu. For example, you can define icons for categories, cms pages, suppliers, manufacturers etc. Moreover, with this modification you can alter settings of main cms category "Home". You can personalize it and its name and also define icon for it.