Understanding the Values Obtained in document.getElementsByClassName

MODAL.methods={
    show:function(elm){
        var$self=elm;
        var$next=$self.nextElementSibling;
        if($next.classList.contains(MODAL.tar)&!$self.classList.contains(MODAL.active)){
            $self.classList.add(MODAL.active);
            $next.classList.add(MODAL.active);

            $next.style.display='block';

            console.log( document.getElementsByClassName(MODAL.active));

            MODAL.methods.overlay();
        }
    },
    close:function(){
        var$close= document.getElementById(MODAL.close);
        console.log( document.getElementsByClassName(MODAL.active));
        Array.prototype.forEach.call( document.getElementsByClassName(MODAL.active), function(elm){
            elm.classList.remove(MODAL.active);
            if(elm.classList.contains(MODAL.tar)){
                elm.style.display='none';
            }
        });
        $close.remove();
    },
    overlay:function(){
        console.log( document.getElementsByClassName(MODAL.active));
        document.body.insertAdjacentHTML('beforeend','<divid="'+MODAL.close+'" class="modal-overlay" onClick="MODAL.methods.close();">span class="modal-overlay_child;>>>>dividan"modal-overlay_>>>>>lt;slide;>>>>>
    }
};