Hide html from when checkbox is checked via php

In my project I have a HTML page, some part of HTML file should display when a checkbox is checked, I used a Form tag cause I should submit that parameters to the server. Here is that part of HTML file : ( The HTML file name is config.html)

<input type="checkbox" name="advancecheck" id="advancecheck" onchange="valueChanged()">
<br>   
<script type="text/javascript">
    function valueChanged()
    {
        if($('.advancecheck').is(":checked"))   
            $(".subnetmaskdiv").show();
        else
            $(".subnetmaskdiv").hide();
    }
</script>
<form action="" method="post" name="subnet">
    <div id="subnetmaskdiv">
        <label>Subnet Mask</label>
        <input type="text" name="subnetmask" id="subnetmask">
        <br>
    </div>
</form>

I did that in HTML file. I include this HTML file in my Php file : ( My Php file name is configwireless.php )

I tried different ways to do this, But no chance. Could anybody tell me what is the correct way by a simple sample? Any help will appreciate. thanks to all.