Feature:

[V0lantis]

Remove div.doctest in basic.css_t so that the selecting feature in snippets code
are not just available for doctests snippets. Basically, I want the following feature :

which is available for every doctest, to be also available for basic snippet code.
For example, in the actual [Sphinx doc](https://www.sphinx-doc.org/en/master/usage/installation.html#installation-from-source), when we select a code's snippet, it also selects the $sign, which is annoying for multi line snippets :

With the modification, we can now do :

This PR is following #9101. I ask for discussion here, because I don't know what was intended span.gp at the first place. From my research, it has been introduced by @tk0miya, in #6727

[tk0miya]

I ask for discussion here, because I don't know what was intended span.gp at the first place.

As the comment in the CSS file says, span.gp means "Generic.Prompt". They're considered as prompt by pygments; a highlighting library.

Note: What I commented in #9101 (comment) is here:

Indeed, it will be helpful for almost of users. But I can't say ALL of the people want to do that. So this would not be changed, I think.

I'm still debating this will not introduce troubles. I'd like to hear comments from @shimizukawa .

[shimizukawa]

I think the prompt will get in the way if it is copied when we want to run the procedure as it is in the sample. The only situations I can think of where we would want to copy text with prompts are: 1) to tell people in chat, etc., or 2) to transcribe the same procedure into a document (including doctest).
In this sense, there are very few situations where we would want to copy and use either the $ symbol or the >>> symbol.

(As a side note, the official Python documentation includes a feature to show/hide the >>> symbol, but I couldn't find a same feature to switch the $ symbol.)

[tk0miya]

@shimizukawa Thank you for your comment.

Okay, let's merge this and wait for user's reaction.

[tk0miya]

Just merged. Thank you for your contribution!