<div class="content">
              <iframe  src="" frameborder="0"  style="position:absolute;   visibility:inherit;   top:0px;   left:0px;   width:expression(this.parentNode.offsetWidth);   height:expression(this.parentNode.offsetHeight);   z-index:-1;   filter='progid:DXImageTransform.Microsoft.Alpha(style=0,opacity=0)';"></iframe>
                  <div class="title">

                      <span class="buttons">

                          <span class="mainstyle"></span>

                      </span>

                 </div> 
               <table style="margin:40px 20px 40px 20px">
                 
                <tr valign="top">
                 
                   <td style="line-height:22px;"><p><b>你已經完成了本單元單詞複習，確定要重新複習嗎

                    </td>
                </tr>
               </table>

          </div>

其實就是在div中新增iframe框架，即新增 <iframe  src="" frameborder="0"  style="position:absolute;   visibility:inherit;   top:0px;   left:0px;   width:expression(this.parentNode.offsetWidth);   height:expression(this.parentNode.offsetHeight);   z-index:-1;   filter='progid:DXImageTransform.Microsoft.Alpha(style=0,opacity=0)';"></iframe>