CSS in Firefox doesnt work

                                 <div class="dd" style="">

[+as.showForm:is=`1`:then=`
<form [+as.formId+] action="[+as.formAction+]" method="post">
<table border="0" cellpadding="0" cellspacing="0">

                               <tr><td valign="top" background="main_imgs/search.png" align="center" valign="middle" style="padding-top:4px;">
<input type="hidden" name="advSearch" value="[+as.advSearch+]" />
<input id="ajaxSearch_input" style="background:none; border:none; display:block; padding-left:10px;" size="16" height="22px" type="text" value="" border="0" name="search" value=""[+as.inputOptions+]>
</td>
<td width="54px" valign="middle">
<input style="background:none; border:none; width:54px; height:22px; background-color:#f8712f; color:#333333; font-size:12px; font-weight:bold;" type="submit" value="Search"></td></tr> </table>
                                </div> 

<!--[if IE]>
<style type="text/css">
 .dd{
     margin-top: 0px;
}
</style>


<link rel="stylesheet" type="text/css" href="style/ie.css" />

<![endif]-->

<script type="text/javascript">
<!--
if(window.opera) {document.write('<link rel="stylesheet" type="text/css" .dd{
     margin-top: 0px; href="style/opera.css" />');}
//-->
</script>

if(window.opera) {document.write('<link rel="stylesheet" type="text/css" .dd{
     margin-top: 0px; href="style/opera.css" />');}

if(window.opera) {document.write('<link rel="stylesheet" type="text/css" href="style/opera.css" />');}