Untitled

!DOCTYPE html>
<html>
<head>
    <title></title>
<script type="text/javascript" src="https://ajax.aspnetcdn.com/ajax/jQuery/jquery-3.4.1.min.js"></script>


</head>
    <body>


        <p id="hide">thank you</p>

        <button id="in">in</button>


        <script type="text/javascript">

            var show = true;

            $("#in").click(function() {
                if (show) {
                      $("#hide").fadeOut(function(){
                          show = false;
                      });
                }else{
                      $("#hide").fadeIn(function(){
                           show = true;
                      });
                }
            });
        </script>
    </body>
</html>