Why Can\'t You Group Descendants in CSS Selectors?

Why Can't You Group Descendants in a CSS Selector?

Traditionally, CSS has lacked an efficient method for applying the same style to a group of descendants. Consider the following HTML table:

<code class="html"><table id='myTable'>
  <tr>
    <th></th>
    <th></th>
    <th></th>
  </tr>
  .
  .
  .
  <tr>
    <td></td>
    <td></td>
    <td></td>
  </tr>
</table></code>

To style both column headings and cells, the traditional selector requires specifying both elements:

<code class="css">#myTable th, #myTable td {}</code>

Why isn't there a more concise syntax like:

<code class="css">#myTable (th,td) {}</code>

Evolution of a Solution

Initially, there was no proposal for a useful syntax until 2008, when the :any() pseudo-class was proposed. Mozilla implemented it as :-moz-any() in 2010, followed by WebKit's :-webkit-any() in 2011.

However, using both prefixes simultaneously necessitated duplicating rulesets, defeating the purpose. As a result, these prefixed selectors are now considered impractical.

The Selectors level 4 working draft now contains a proposal for :matches(), based on the original :any() but with potential enhancements. However, browser support is expected to take some time.

Workarounds

For styling both th and td elements specifically, you can use * instead, assuming that the tr elements contain only cell elements:

<code class="css">#myTable tr > * {}</code>

Alternatively, for performance reasons, you may prefer the longer traditional method.

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