<script>
    $(".content-item").hover(
        function () { $(this).addClass("bounce") },
        function () { $(this).removeClass("bunce") }
    );
      </script>

<div class="content-item">
  <div><span>Lorem ipsum do sit</span>
        <div class="bye_cruize wow">
            <a href="#"><span>BYE CRUIZE</span></a>
        </div>
    </div>
</div>

$(".content-item").hover(function () {
  $(this).children().children().toggleClass("bounce");
});