Table Header styles not applied
I am working in a project that was converted from RH2019 Classic and is now running on RoboHelp 2020.6.76. I have some table style updates I want to apply and these will work best if I can use the table header functionality. But right now when I click "Convert to Header" the style that is being applied is not the style I want.
This is what my table looks like right now with the header manually formatted using a paragraph style.

And this is what I see when I select "Convert to Header":

It keeps my formatting for the words, but the table loses its borders completely.
Here's what I have for the css. I duplicated the table border formatting in an attempt to get them to display correctly:
table.SimpleGridSilver tr th {
font-weight: bold;
text-align: left;
color: #000000;
border-width: 1px;
border-color: #C0C0C0;
border-left-width: 1px;
border-left-color: #C0C0C0;
border-top-width: 1px;
border-top-color: #C0C0C0;
border-right-width: 1px;
border-right-color: #C0C0C0;
border-bottom-width: 1px;
border-bottom-color: #C0C0C0;
margin-top: 5pt;
margin-bottom: 5pt;
padding-top: 2pt;
padding-right: 2pt;
padding-bottom: 2pt;
padding-left: 2pt;
height: 39px;
}
And lastly, here is the html for my table:
<tbody>
<tr>
<th>
<p>Field</p>
</th>
<th>
<p>Additional information</p>
</th>
</tr>
Any suggestions for where this style might be kept or something I can do to get my settings to stick?
