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<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>无标题文档</title>
</head><body>
<table width="770" border="0" align="center" cellpadding="0" cellspacing="0">
  <tr>
    <td height="60"><img src="../images/logo_mail.gif" width="197" height="54" /></td>
  </tr>
  <tr>
    <td height="24" class="nav">邮箱续费</td>
  </tr>
  <tr>
    <td height="1" bgcolor="#E6E6E6"><div align="center"></div></td>
  </tr>
  <tr>
    <td height="15" bgcolor="#FFFFFF"><div align="center"></div></td>
  </tr>
</table>
<table width="770" border="0" align="center" cellpadding="0" cellspacing="0">
  <tr>
    <td colspan="2" class="linetd"><div align="center"></div></td>
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  <tr>
    <td height="26" colspan="2" bgcolor="#EFEFEF" class="bor">选择支付方式：&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="red bl">续费邮箱： [email protected]&nbsp;&nbsp;  &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;产品价格：10 元/月</span> </td>
  </tr>
</table>
<table width="770" border="0" align="center" cellpadding="0" cellspacing="0" bgcolor="#F9F9F9">
  <tr>
    <td width="25%" height="50" align="center" class="fsize14"><script language="JavaScript" type="text/javascript">
    function check(flag){
        if(flag == 1){
document.getElementById("mobile").style.display="inline";
            document.getElementById("internet").style.display="none";
            document.getElementById("post").style.display="none";
document.getElementById("other").style.display="none";
        }else if(flag == 2){
            document.getElementById("mobile").style.display="none";
            document.getElementById("internet").style.display="inline";
            document.getElementById("post").style.display="none";
document.getElementById("other").style.display="none";
        }
else if(flag == 3){
            document.getElementById("mobile").style.display="none";
            document.getElementById("internet").style.display="none";
            document.getElementById("post").style.display="inline";
document.getElementById("other").style.display="none";
        }
else if(flag == 4){
            document.getElementById("mobile").style.display="none";
            document.getElementById("internet").style.display="none";
            document.getElementById("post").style.display="none";
document.getElementById("other").style.display="inline";
        }
    }
</script>
        <label>
        <input type="radio" name="pay" value="1" onclick="check(1)" />
          手机支付 (推荐)</label></td>
    <td width="25%" align="center" class="fsize14"><input type="radio" name="pay" value="2" onclick="check(2)" />
      网上支付</td>
    <td width="25%" align="center" class="fsize14"><input name="pay" type="radio" value="3" onclick="check(3)" />
      邮局汇款</td>
    <td width="25%" align="center" class="fsize14"><input type="radio" name="pay" value="4" onclick="check(4)" />
      其他支付方式</td>
  </tr>
</table>
<table width="770" border="0" align="center" cellpadding="0" cellspacing="0" bgcolor="#F9F9F9">
  <tr>
    <td align="center"><div id="mobile" class="intropay" style="display:none">
      <table width="100%" border="0" align="center" cellpadding="5" cellspacing="0">
        <tr>
          <td class="fsize13b">请输入手机号码：
            <input name="textfield3" type="text" class="input1" size="20" onfocus="this.style.backgroundColor='#f2f2f2';" onblur="this.style.backgroundColor='';" /></td>
        </tr>
        <tr>
          <td>注：只支持移动用户。</td>
        </tr>
      </table>
    </div>
        <div id="internet" class="intropay" style="display:none">
          <table width="100%" border="0" align="center" cellpadding="5" cellspacing="0">
            <tr>
              <td class="fsize13b">请选择交费银行：</td>
            </tr>
            <tr>
              <td><input type="radio" name="radiobutton" value="radiobutton" />
                工商银行</td>
            </tr>
            <tr>
              <td><input name="radiobutton" type="radio" value="radiobutton" />
                招商银行</td>
            </tr>
            <tr>
              <td><input type="radio" name="radiobutton" value="radiobutton" />
                首信支付（建设银行 / 农业银行 / 北京银行）</td>
            </tr>
            <tr>
              <td><input type="radio" name="radiobutton" value="radiobutton" />
                银联支付（民生银行 / 浦发银行&nbsp;/ 光大银行）</td>
            </tr>
          </table>
          <br />
          <table width="100%" border="0" align="center" cellpadding="5" cellspacing="0">
            <tr>
              <td class="fsize13b">目前网上支付只支持年付。请您确认支付时间：</td>
            </tr>
            <tr>
              <td><input type="radio" name="radiobutton" value="radiobutton" />
                120元/ 12个月</td>
            </tr>
            <tr>
              <td><input name="radiobutton" type="radio" value="radiobutton" checked="checked" />
                240元/ 24个月</td>
            </tr>
            <tr>
              <td><input type="radio" name="radiobutton" value="radiobutton" />
                360元/ 36个月 </td>
            </tr>
          </table>
        </div>
      <div id="post" class="intropay" style="display:none">
          <table width="100%" border="0" align="center" cellpadding="5" cellspacing="0">
            <tr>
              <td class="fsize13b">目前邮局汇款只支持年付。请您确认支付时间：</td>
            </tr>
            <tr>
              <td><input type="radio" name="radiobutton" value="radiobutton" />
                120元/ 12个月</td>
            </tr>
            <tr>
              <td><input name="radiobutton" type="radio" value="radiobutton" checked="checked" />
                240元/ 24个月</td>
            </tr>
            <tr>
              <td><input type="radio" name="radiobutton" value="radiobutton" />
                360元/ 36个月 </td>
            </tr>
          </table>
      </div>
      <div id="other" class="intropay" style="display:none">
          <table width="100%" border="0" align="center" cellpadding="5" cellspacing="0">
            <tr>
              <td class="fsize13b">其他付款方式：</td>
            </tr>
            <tr>
              <td><input type="radio" name="radiobutton" value="radiobutton" />
                互联星空支付</td>
            </tr>
            <tr>
              <td><input name="radiobutton" type="radio" value="radiobutton" checked="checked" />
                北京通信支付（北京通信ADSL / LAN / 16900 / 96369用户可通过上网帐号付款）</td>
            </tr>
          </table>
      </div></td>
  </tr>
</table>
<table width="770" border="0" align="center" cellpadding="0" cellspacing="0" bgcolor="#F9F9F9">
  <tr>
    <td height="50" align="center" valign="middle"><input name="Submit22" type="button" class="button1" value=" 下 一 步 " onclick="window.open('#2','_self')" /></td>
  </tr>
</table>
</body>
</html>
整体功能效果是这样的，谢谢，谁能帮我优化一下JS代码，不胜感激！