如何从弹出窗口向数据库存储多个值?

i am trying to use a popup window using css that accepts multiple values. For example, when I click on a particular link a new window appears with multiple input boxes. My question is how to store accepted values in database?

I am using php as server side scripting language. A simple example to illustrate the concept would be appreciated.

 <html>
 <head>
 </head>

 <style>
 #overlay {
 visibility: hidden;
 position: absolute;
 left: 0px;
 top: 0px;
 width:100%;
 height:100%;
 text-align:center;

 }


 #overlay div {
 width:300px;
 margin: 100px auto;
 background-color: #fff;
 border:1px solid #000;
 padding:15px;
 text-align:center;
  }

</style>


 <div id="overlay">
 <div>
    <p><input type="text" id=txt name=txt /></p>
  <input type="submit" onclick="add()" />[<a href='#' onclick='overlay()'>close</a>]
 </div>
 </div>
 <a href='#' onclick='overlay()'>clck here</a>
 <script>

 function add()
 {
   alert(document.getElementById("txt").value)  

 }


  function overlay() {
el = document.getElementById("overlay");
el.style.visibility = (el.style.visibility == "visible") ? "hidden" : "visible";
 }
</script>

 <body>
 </body>
 </html>