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<div class="album-c">
    <a href="javascript: jQuery.fancybox.close()" class="closeBtn pull-right"><i class="glyphicon glyphicon-remove"></i></a>
    <h2><span>OSA Course</span></h2>
    <div class="gallery-album"><div class="image active"><div class="l"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-1-800x600.jpg"></div><div class="r"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-1-800x600.jpg"></div><div class="clearfix"></div></div><div class="image to-right"><div class="l"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-3-800x600.jpg"></div><div class="r"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-3-800x600.jpg"></div><div class="clearfix"></div></div><div class="image to-right"><div class="l"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-16-800x600.jpg"></div><div class="r"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-16-800x600.jpg"></div><div class="clearfix"></div></div><div class="image to-right"><div class="l"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-17-800x600.jpg"></div><div class="r"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-17-800x600.jpg"></div><div class="clearfix"></div></div><div class="image to-right"><div class="l"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-25-800x600.jpg"></div><div class="r"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-25-800x600.jpg"></div><div class="clearfix"></div></div><div class="image to-right"><div class="l"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-27-800x600.jpg"></div><div class="r"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-27-800x600.jpg"></div><div class="clearfix"></div></div><div class="image to-right"><div class="l"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-28-800x600.jpg"></div><div class="r"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-28-800x600.jpg"></div><div class="clearfix"></div></div><div class="image to-right"><div class="l"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-29-800x600.jpg"></div><div class="r"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-29-800x600.jpg"></div><div class="clearfix"></div></div><div class="image to-right"><div class="l"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-30-800x600.jpg"></div><div class="r"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-30-800x600.jpg"></div><div class="clearfix"></div></div><div class="image to-right"><div class="l"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-31-800x600.jpg"></div><div class="r"><img src="https://www.bscoso.com/wp-content/uploads/2021/11/Photos-31-800x600.jpg"></div><div class="clearfix"></div></div><a href="#" id="toLeft" class="pull-left nav-left"><i class="glyphicon glyphicon-chevron-left"></i></a><a href="#" id="toRight" class="pull-right nav-right"><i class="glyphicon glyphicon-chevron-right"></i></a></div>
    <script>
        jQuery(function($) {
            var $images = $(".gallery-album .image");
            var currentIndex = 0;
            $images.each(function(index){
               $(this).css("z-index", $images.length - index);
            });
            $("#toLeft").click(function (e) {
                e.preventDefault();
                if(currentIndex<=0) return;
                $images.eq(currentIndex).removeClass("active").addClass("to-right").index();
                currentIndex--;
                $images.eq(currentIndex).removeClass("to-left").addClass("active");
                checkArrows();

            });
            $("#toRight").click(function (e) {
                e.preventDefault();
                if(currentIndex >= $images.length-1) return;

                $images.eq(currentIndex).removeClass("active").addClass("to-left").index();
                currentIndex++;
                $images.eq(currentIndex).removeClass("to-right").addClass("active");
                checkArrows();
            });
            $(".gallery-album").parents(".fancybox-overlay").keyup(function(e){
                if(e.keyCode == 39) $("#toRight").click();
                else if(e.keyCode == 37) $("#toLeft").click();
            })

            function checkArrows(){
                if(currentIndex<=0){
                    $("#toLeft").hide();
                }else{
                    $("#toLeft").show();
                }
                if(currentIndex >= $images.length-1){
                    $("#toRight").hide()
                }else{
                    $("#toRight").show()
                }
            }
            checkArrows();
            $("#toRight").focus();
        });
    </script>
</div>