Use the new utility
.bg-transparent in combination with
.navbar-light for placing navbars over backgrounds and interactive content.
You can add nested submenus by inserting a
.dropdown.dropdown-submenu as an item inside a
.dropdown-menu, because we're just reusing the same classes to create each nested submenu, there's no limit to how many steps you can get, and it comes optimized for mobile devices too :D
You can change the style of one or all dropdown menus to a dark version.