как сделать при закрытия вкладки сайта?

    <script src="{THEME}/js/jquery.cookie.js" type="text/javascript"></script>
<script>
(function($){
    function showPopup (){
        $('#b-close').fadeIn(200);
        $('#b-close-bg').fadeIn(300);
    }
        setTimeout(function(){
        var previousY;
        if (window.innerWidth > 1000 && (!$.cookie("__close") || 0))
        {
            $(document).bind("mousemove", function (e)
            {
                if (e.clientY <= 10)
                {
                    if(!previousY && e.clientY)
                        previousY = e.clientY;
                    if(($("#b-close").css("display") != "block") && previousY > e.clientY)
                    {
                        if (!$.cookie("__close") || 0)
                            showPopup();
                        $(document).unbind("mousemove");
                        $.cookie("__close", 1, { expires: 1, path: '/'});
                    }
                }
            });
        }
    }, 30000);
 }) (jQuery);
</script>
<style>
    #b-close-bg {
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        position: fixed;
        z-index: 10000;
        background: rgba(0, 0, 0, 0.9);
        cursor: pointer;
        display: none;
    }
    #b-close {
        z-index: 10001;
        position: fixed;
        top: 100px;
        left: 50%;
        width: 1000px;
        margin-left: -500px;
        border-radius: 8px;
        box-shadow: 0 0 10px rgba(255, 255, 255, 0.5);
        background: white;
        display: none;
    }
    .b-close-window_close {
        font-size: 45px;
        float: right;
        margin: 0 10px;
        cursor: pointer;
        position: relative;
        z-index: 1;
    }
    .b-close-window_title {
        font-size: 26px;
        text-align: center;
        margin: 30px 0 0 0;
        color: #007EFF;
    }
    .b-close-post-list {
        float: left;
        width: 44%;
        margin: 30px;
    }
    .bclose-hog-image {
        position: absolute;
        margin: 10px;
    }
</style>
<div id="b-close-bg" style="" onclick="$('#b-close').fadeOut(200); $('#b-close-bg').fadeOut(300);"></div>
<div id="b-close" style="">
    <div class="b-close-window_close" onclick="$('#b-close').fadeOut(200); $('#b-close-bg').fadeOut(300);">×</div>
    <div class="b-close-window_title">ЗАГОЛОВОК</div>
    <div class="b-close-window">
    <div class="b-close-post-list clearfix">
ТУТ СВОЙ КОНТЕНТ
        </div>
    </div>
</div>