Accordion menu for mobile / Regular vertical menu for medium up

Hi everyone,
I have this really simple menu which I want to behavior as I put on the title of this tread. There´s this synthax that I believe to be the logic behind the behavior that I want: data-responsive-menu=“accordion medium-dropdown”; in other words “for mobile go Accordion / for medium up go dropdown”. Instead of Dropdown I want it to be a simple vertical menu. I changed the value “dropdown” to “vertical menu” but it didin´t work.

Do I have to rethink the logic behind this behavior or is it just a simple matter of naming the right stuff? My code bellow:

    <ul class="vertical medium-vertical menu" data-responsive-menu="accordion medium-vertical menu">
            <li>
            <a href="#">Main</a>
                <ul class="vertical menu">
                    <li><a href="#">Item 1A</a></li>
                    <li><a href="#">Item 1B</a></li>
                    <li><a href="#">Item 1C</a></li>
                    <li><a href="#">Item 1D</a></li>
                </ul>
            </li>
        </ul>

Thank you! Cheers!