check if outside the div is clicked

JavaScript
$(document).mouseup(function(e) 
{
    var container = $("YOUR CONTAINER SELECTOR");

    // if the target of the click isn't the container nor a descendant of the container
    if (!container.is(e.target) && container.has(e.target).length === 0) 
    {
        container.hide();
    }
});
Source

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