<script type="text/javascript">


            $("a").click(function () {
                clearClass();
                $(this).addClass("bg_color");
            });
            function clearClass() {
                $("a").each(function () {
                    $(this).removeClass("bg_color");
                });
            }

        </script>




 <style type="text/css">
        .bg_color
        {
            cursor:pointer;//鼠标显示效果,小手

            color:Red;

            font-weight:bold;//加粗

        }
</style>