Is it possible to pass parameters in JQuery popup box??

there has two file
form.php <--The user will fill in the form like username.
when the form sumbit, it have a JQUERY pop up box to show his username that is the user fill in the form.

THX
My html code

```
<form method="get" onsubmit="return false;">
    First name:<br>
    <input name="firstname" type="text"><br>
    <br>
    <input type="submit" value="Submit" onclick="popupfunctioncall();">
</form>
<div class="popup-container">
    <div class="popup-play"></div>
    <div class="pop-popup white_content" id="light">
        <div class="popup-close">
            <span><font size="5">x</font></span>
        </div><?php 
        echo $_GET["firstname"];

        ?>
    </div>
    <div class="black_overlay" id="fade"></div>
</div>

```

MY Css code

```
.black_overlay {
display: none;
position: absolute;
top: 0%;
left: 0%;
width: 100%;
height: 100%;
background-color: black;
z-index: 1001;
-moz-opacity: 0.8;
opacity: .80;
filter: alpha(opacity=80);}

.white_content {
display: none;
position: absolute;
top: 0px;
right: 0;
left: 0;
bottom: 0;
margin: auto;
height: 500px;
width: 600px;
background-color: #ffffff;
z-index: 1002;
background-color: #fff;
z-index: 1002;
overflow: auto;
text-align: center;}

.popup-close {
position: absolute;
top: -2px;
right: 7px;}

```

My Javascript code

```
function popupfunctioncall(){
    $('#light').fadeIn(600);
    $('#fade').fadeIn(600);
}

    $(document).on('click','.popup-close',function(){
    $('#light').fadeOut(600);
    $('#fade').fadeOut(600);
}); 

```