表头固定垂直滚动在IE 11中不起作用

Question

请......我需要帮助这个...... 我有一个固定和垂直滚动的表格的代码，工作正常：

<style type='text/css'>
div.fixedHeaderTable table {  border-spacing: 0;
                             display: flex;
                             max-height: 180px;
                             overflow-y: auto;
                             overflow-x: hidden;
                             table-layout: fixed;
                             width: 98vw;
                             border:1px 
                             solid gray;
                          }
div.fixedHeaderTable thead {  font-family: Verdana;
                             color: #FFFFFF;
                             background-color: #f1eee9;
                             position: fixed !important;
                          }
div.fixedHeaderTable th    {  background-color:#CCCCCC;
                             background-color:#DA291C;
                             border-bottom: 1px solid #c4c0c9;
                             border-right: 1px solid #c4c0c9;
                          }
div.fixedHeaderTable th, div.fixedHeaderTable td { text-align: center;
                                                  font-family: Verdana;
                                                  font-weight: bold;
                                                  margin: 0;
                                                  max-width: 18.5vw;
                                                  min-width: 18.5vw;
                                                  word-wrap: break-word;
                                                  font-size: 10px;
                                                  height: 25px !important;
                                                  padding: 2px;
                                                  border-right: 1px solid #c4c0c9;
                                                }
div.fixedHeaderTable tr:nth-child(2n) {   background: none repeat scroll 0 0 #edebeb;}
</style>

<div class='fixedHeaderTable'>
<table>
  <thead>
     <tr>
        <th>Fecha Despacho</th>
     </tr>
  </thead>
  <tbody>
     <tr style='height: 40px;'><td></td></tr>
     <tr><td>Viernes, 28/04/2017  </td></tr>
     <tr><td>Sábado, 29/04/2017   </td></tr>
     <tr><td>Domingo, 30/04/2017  </td></tr>
     <tr><td>Lunes, 01/05/2017    </td></tr>
     <tr><td>Martes, 02/05/2017   </td></tr>
     <tr><td>Miércoles, 03/05/2017</td></tr>
     <tr><td>Jueves, 04/05/2017   </td></tr>
     <tr><td>Viernes, 05/05/2017  </td></tr>
     <tr><td>Sábado, 06/05/2017   </td></tr>
     <tr><td>Domingo, 07/05/2017  </td></tr>
     <tr><td>Domingo, 28/05/2017  </td></tr>
  </tbody>
</table>
</div>

它在Chrome，FireFox等方面的表现非常出色......但它在IE中不起作用。

任何sugestions ......

请帮帮我...... 感谢。