>
              <dfn>`titlebar-area-x`</dfn>
            </td>
            <td>
              <a href=
              "https://drafts.csswg.org/css-values-3/#length-value">length</a>
            </td>
          </tr>
          <tr>
            <td>
              <dfn>`titlebar-area-y`</dfn>
            </td>
            <td>
              <a href=
              "https://drafts.csswg.org/css-values-3/#length-value">length</a>
            </td>
          </tr>
          <tr>
            <td>
              <dfn