Oh yesI I would recommend doing it in your theme. If you use, say the Firebug Firefox extension, you can view the generated HTML in the page:
<table class="mz-schedule-filter">
<tfoot>
<tbody>
<tr class="header">
<th class="mz_date_display" scope="header">Thu August 13</th>
<th class="mz_classDetails" scope="header">Class Name</th>
<th class="mz_staffName" scope="header">Instructor</th>
<th class="mz_sessionTypeName" scope="header">Class Type</th>
</tr>
</tbody>
You can use those classes to set coloring, font, etc. It’s a bootstrap table so as long as your theme doesn’t conflict, that may be useful.
You could also use jQuery onload events to make more advanced changes. And feel free to reach out to me via mZoo.org, but will be away through the weekend.