Main Menu with Arrows but Dropdown Menus with arrows

Hi there,
thanks to your help we could figure out how to set up arrows for the main menu. But when you open one of the dropdown menus, we have submenus where we need arrows to point out that there is more in the sub-menu. But how do we set this up?

This is the code we are using at the moment:

/* Main Menu: Disable arrows */

.menu-item-has-children .dropdown-menu-toggle {
display: none;
}

.main-navigation .main-nav ul li.menu-item-has-children > a {
padding-right: 20px;
}

/* Menu Style */

ul.sub-menu.toggled-on {
margin-top: 15px;
}

.sticky-social-icons {
position: fixed;
right:0;
top: 30%;
}

Please see the page and screenshots in the private information are.

Thanks