$("#contact_form").on("submit", function(e) {
        e.preventDefault();

        $("#cbtn").css('background-color', 'grey');

        var captcha_code = $('#captcha_code').val();
        var captcha = $('#captcha').val();
        
        var cource1 = $('input[name=courses1]:checked').map(function(){
            return $(this).val();
        }).get();
        var cource2 = $('input[name=courses2]:checked').map(function(){
            return $(this).val();
        }).get();
        var cource3 = $('input[name=courses3]:checked').map(function(){
            return $(this).val();
        }).get();
        var cource4 = $('input[name=courses4]:checked').map(function(){
            return $(this).val();
        }).get();
        var cource5 = $('input[name=courses5]:checked').map(function(){
            return $(this).val();
        }).get();
        var cource6 = $('input[name=courses6]:checked').map(function(){
            return $(this).val();
        }).get();
        
        if(captcha_code == captcha) {
            $.ajax({
                url: "contact_mail.php",
                type: "POST",
                data: $(this).serialize() +"&cource1=" + cource1 + "&cource2=" + cource2 +"&cource3=" + cource3 +"&cource4=" + cource4 +"&cource5=" + cource5 +"&cource6=" + cource6,
                // dataType: 'JSON',
                success: function(data) {
                    // console.log(data);
                    // $("#contact_form")[0].reset();
                    // swal("Awesome!","Contact us form submitted successfully !","success");
                    // $('#cbtn').removeAttr("style");
                    // $('#cbtn').addClass("comment_button trans_200");

                    var obj = jQuery.parseJSON(data);
                    // console.log(obj);
                    if(obj.success === false) {
                        if(obj.code === "1") {
                            // email not sent
                            swal("Oops...", "Email is not sent", "error");
                        } else if(obj.code === "3") {
                            // required filed
                            swal("Oops...", "Please fill all the required fields", "error");
                        }
                    } else {
                        // Successfully
                        $("#contact_form")[0].reset();
                        swal("Awesome!","Contact us form submitted successfully !","success");
                        $('#cbtn').removeAttr("style");
                        $('#cbtn').addClass("comment_button trans_200");
                    }
                }
            });
        } else {
            swal("Oops...", "Captcha code is wrong!", "error");
        }
    });