rustdoc styling issue: `.docblock` occasionally has problematic right padding

[davidbarsky]

In tracing, we use warnings blocks to surface potential gotchas to users (this is arguably a misuse of blocks in rustdoc, but anyways...). Unforuntately, I noticed that blocks add 1ex of right padding to anything rendered as code, including inline comments. Here's an example: https://deploy-preview-1430--tracing-rs.netlify.app/tracing/struct.span#method.entered. A screenshot is below for posterity.

The extra right padding results in a poor reading experience while reading some of tracing's documentation. While I recognize that we're misusing docblocks to render tooltips and #83550 attempted to solve this problem in more well-trodden use-cases, I was hoping that this rendering issue could either be fixed or we can be given a decently stable workaround. Thanks!

Meta

rustc --version --verbose:

❯ rustc --version --verbose
rustc 1.54.0-nightly (e4a603270 2021-06-07)
binary: rustc
commit-hash: e4a60327063e82413eed50a10df3b7d19b77bda0
commit-date: 2021-06-07
host: x86_64-apple-darwin
release: 1.54.0-nightly
LLVM version: 12.0.1

[jyn514]

I agree this is not super supported ... cc @jsha in case you want to take a look, but I'm not sure we want to fix it.

[davidbarsky]

A fix isn't really strictly necessary. If we can provide custom CSS to rustdoc and docs.rs where we override .docblock with a tracing-specific selector (or a similar, tracing-scoped approach), that'd also be a great resolution.

[GuillaumeGomez]

I think it's somewhat related to #79677.

[jyn514]

If we can provide custom CSS to rustdoc and docs.rs where we override .docblock with a tracing-specific selector (or a similar, tracing-scoped approach), that'd also be a great resolution.

@davidbarsky Missed this before sorry - this is already stable: https://doc.rust-lang.org/stable/rustdoc/command-line-arguments.html#-e--extend-css-extend-rustdocs-css

[jyn514]

I'm going to close this since there's a stable workaround.