我可以用javascript增强复杂表的可访问性吗?

table { border: 1px solid black; border-collapse:collapse; width: 100%; }
td, th { border: 1px solid black; }
th { background-color: lightgray; }

<!-- simplified table -->
<table>
  <thead>
    <tr><th></th><th>Col 1</th><th>Col 2</th></tr>
  </thead>
  <tbody>
    <tr><th>Row 1</th><td>Foo</td><td>Bar</td></tr>
    <tr><th colspan="3">Header for subregion</th></tr>
    <tr><th>Row 2</th><td>Foo</td><td>Bar</td></tr>
    <tr><th>Row 3</th><td>Foo</td><td>Bar</td></tr>
  </tbody>
</table>