Gmail HTML email, neon blue behind a linked image

Hi

Im hoping someone can help me with this, I have tried everything I know and read all the articles I could find on the net. Nothing has worked 😞

Basically, there is what seems to be a neon blue background colour showing up ONLY in Gmail in the <td> containing the header image in my email. A screenshot is attached (Blue-line-image.PNG).

The table code is below:

<table border="0" cellspacing="0" class="body-wrap" bgcolor="#FFFFFF" style="max-width: 600px">

  <tbody>

    <tr>

      <td align="center" class="container" bgcolor="=FFFFFF" style="padding: 0px; margin: 0px; line-height:10px; font-size:6px">

    <div class="container1"><a href="http://www.rolla.com" style="text-decoration: none; border: none"><img src="https://rolla.igamingcloud.com/Images/Emails/MailSystem/Upload/rolla_system_header.gif" align=“absbottom”  width="100%" style="display:block; max-height: 172px; max-width: 600px; border:none; padding: 0px; margin 0px" border="0" alt="Rolla Casino Logo"/></a></div>

        </td></tr></tbody></table>

AS you can see I have specified background colour of white in the table and td.  I have added style attributes to the border (and other tips I found on the net) to the href and img tags. None of these has worked 😞

The classes "container" and "container1" both contain:

border-width:0 none;

    background: #ffffff;

    text-decoration: none;

    text-decoration-color: #ffffff;

Even when I unlinked the header image and sent another test, the blue was there! Please see screenshot "Blue-line-text.PNG"

Please help!

Thanks

Michael