Fix media queries with jit and postcss7

[jscissr]

When using @tailwindcss/postcss7-compat and jit, media queries are not generated.

The problem is that this chunk of code: https://github.com/postcss/postcss/blob/8.2.10/lib/node.js#L44-L48
is missing in postcss 7: https://github.com/postcss/postcss/blob/7.0.35/lib/node.es6#L37
Which means that the parent of the rule is not set correctly, which then causes this bug.

This fixes #4034.

[codecov-commenter]

Codecov Report

Merging #4078 (d889791) into master (b442c91) will decrease coverage by 0.01%.
The diff coverage is 75.00%.

❗ Current head d889791 differs from pull request most recent head 7324128. Consider uploading reports for the commit 7324128 to get more accurate results

@@            Coverage Diff             @@
##           master    #4078      +/-   ##
==========================================
- Coverage   86.84%   86.83%   -0.02%     
==========================================
  Files         341      341              
  Lines        4835     4838       +3     
  Branches      919      920       +1     
==========================================
+ Hits         4199     4201       +2     
- Misses        561      562       +1     
  Partials       75       75              

Impacted Files	Coverage Δ
jit/lib/generateRules.js	92.45% <75.00%> (-0.50%)	⬇️

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[bradlc]

Amazing, thank you! ❤️

[gilesbutler]

Awesome work, thanks guys 👍

[dave-calleja]

I still seem to have the same issue even after upgraded to 2.1.2. Using @tailwindcss/postcss7-compat. Am I missing something?

[kb1995]

@dave-calleja I have the same issue. I'm using @tailwindcss/postcss7-compat and updated to latest version, but classes such as flex are not working for me

pinging @bradlc

[adamwathan]

Hey! Please create a new issue and include a minimal reproduction, we don't actively monitor closed issues/PRs.