如何在td标签中响应图像大小?

我在相对复杂的表结构中和td标签中有一个图像。我正在尝试做出图像响应,以便在移动设备上查看页面时,与在台式机上查看时相比,图像略有缩小,即理想情况下,我希望它是宽度页面的50%。

I've tried adding a max-width on the img tag as well as the tg tag outside it and neither appeared to work.

我的代码:

<html>
    <table bgcolor="#efefef" width="100%" border="0" align="center" cellpadding="0" cellspacing="0">
      <tr>
        <td valign="top">
        <!--[if (gte mso 9)|(IE)]>
        <table width="600" align="center" cellpadding="0" cellspacing="0" border="0"><tr><td valign="top">
        <![endif]-->
        <table width="100%" class="maxW" style="max-width: 600px; margin: auto;" border="0" align="center" cellpadding="0" cellspacing="0">
          <tr>
            <td valign="top" align="center">
                <table width="100%" border="0" cellpadding="0" cellspacing="0" bgcolor="#FFFFFF">
                    <tr>
                    <td align="center">
                        <table width="94%" border="0" cellpadding="0" cellspacing="0" style="padding-bottom:10px">
                            <tr>...</tr>
                            <tr>...</tr>
                            <tr>...</tr>
                        </table>
                    </td>
                    </tr>                         

                    <tr>
                    <td align="center">
                        <table width="94%" border="0" cellpadding="0" cellspacing="0" style="padding-bottom:10px">
                            <tr>...</tr>
                            <tr>...</tr>
                            <tr>...</tr>
                        </table>
                    </td>
                    </tr>

                    <tr>
                        <td align="left" valign="middle" style="font-family:Helvetica, Arial, sans-serif; font-size: 12px; color: #353535; padding:3%; padding-top:5px; padding-bottom:5px;">
                            .........
                        </td>
                    </tr>

                    <tr>
                        <td align="center" valign="middle" style="padding:1%; padding-top:10px; padding-bottom:5px;"><a href="https://www.google.com/images/branding/googlelogo/1x/googlelogo_color_272x92dp.png"><img src="https://www.google.com/images/branding/googlelogo/1x/googlelogo_color_272x92dp.png" style="max-width: 50%"></img></a></td>
                    </tr>
        
                </table>
            </td>
          </tr>
        </table>
        <!--[if (gte mso 9)|(IE)]>
        </td></tr></table>
        <![endif]-->
        </td>
    </tr>
    </table>
</html>