css trick to disable parallax effect on phones- help please :  

    //html code for parallax - help required here. I have added div for parallax with name parallax and parallax css in stylesheet. please note. any help in disabling it for the mobile and desktop view will be appreciated.Thanks. I had gone through numerous posts but no help.
but I don't want it to be disabled for desktop. I just want it to stop working for the mobile. Can something be done about it?
      
        	</head>
      <style>
//parallax code

    .parallax { 
        /* The image used */
        margin-top: 30px;
        background-image: url("images/teodorik-mensl-316897-unsplash.jpg");
        /* Set a specific height */
        height: 500px; 
        /* Create the parallax scrolling effect */
        background-attachment: fixed;
        background-position: center;
        background-repeat: no-repeat;
        background-size: cover;
    }
    </style>
    <body>
    //parallax declaration
    <div id="PaperCall" class="parallax"></div>
    </body>
any suggestions will be appreciated.


