calling external js file function in javascript/jquery of html page

I have a html page with a bit of javascript that applies to a button......

$('.iconM-testimonials').on('click', function () {

    $("#colorscreen").remove()

    $("body").append('<div id="colorscreen" class="animated"></div>')

    $("#colorscreen").addClass("fadeInUpBig");

    $('.fadeInUpBig').css('background-color', 'rgba(164, 196, 0, 0.3)');

    $(".tile-group.main").css({ width: "720px"}).load("musability-musictherapy-company-overview.html");

});

It is attached to a button that is within a menu that pops out and has its own js file to make sure this happens... here is an extract of the open/close function within the external js file....

// open (or close) the menu

this.trigger.addEventListener( this.eventtype, function( ev ) {

    ev.stopPropagation();

    ev.preventDefault();

    if( self.open ) {

        self._resetMenu();

    } else {

        self._openMenu();

        // the menu should close if clicking somewhere on the body (excluding clicks on the menu)

        document.addEventListener( self.eventtype, function( ev ) {

            if( self.open && !hasParent( ev.target, self.el.id ) ) {

                bodyClickFn( this );

            }

        });

    }

});

Basically I want to ammend the first javascript function to include a "close the menu" bit when it has executed the functions like colorscreeen.remove etc.... any help on this would be great as I don't even know if i can do this.

the html has a button currently that opens and closes the menu here is that html....

<div class="navbtn">

    <a href="#" id="trigger" class="menu-trigger">Menu</a>

</div>