Use below given attribute to set Hovered sidebar style(Not applicable in horizontal layout).

How to add new menu items/change menu items?

You can simply use copy paste the resources/views/layouts/layouts-vertical-hovered.blade.php code into the master.blade.php to make changes in all the pages.

In order to add, change or remove menu items from the left side navigation, simply edit in file resources/layouts/sidebar.blade.php. The change would reflect in all the files automatically.