Question:
My code, line 22, 36 and 37:
22: <th id="Name">Name</th>
36: <th colspan="2" rowspan="4" id="Terrestrial-planets">Terrestrial planets</th>
37: <th id="Mercury">Mercury</th>
Would it be a mistake to make line 37 like this: <th id="Mercury" headers="Terrestrial-planets Name">Mercury</th>
Or for <th> it is incorrect to set “headers”?
Great job on this exercise. Everything looks correct.
Regarding your question, I think this would be a good idea, because headers is also allowed on <th>.
On a general note: I would recommend using the scope attribute on the <th>s instead of headers on the <td>s. That would have saved you a lot of typing.
Here are two examples:
<th scope="col">Diameter (km)</th> We tell the browser/screen reader that this header applies to the column
<th rowspan="4" colspan="2" scope="rowgroup">Terrestrial planets</th> This header applies to a group of rows (since we have a rowspan attribute)
I hope that helps. Feel free to ask more questions, if something is unclear.