function getElementBefore(_el,_class) {
    var _parent = _el;
    do {
        _parent = _parent.parentNode;
    }
    while(_parent && _parent.tagName.toUpperCase() != "HTML" &&  !( new RegExp( '(^|\\s)' + _class + '(\\s|$)' ) ).test( _parent.className ) )
    return _parent;
}