リスト要素に対して番号を振りたければ list-style-type: decimal を使えば良いんですが、テーブルだとそうもいかないです。しかし行番号を振るためだけに JavaScript は使いたくない。 そういうときは CSS Counters を使います。 <table> <thead> <tr> <th></th> <th>column1</th> <th>column2</th> </tr> </thead> <tbody> <tr> <td></td> <td>foo</td> <td></td> </tr> <tr> <td></td> <td>bar</td> <td></td> </tr> <tr> <td></td> <td>baz</td> <td></td> </tr> </tbody> </table>
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