fix(curriculum-helpers): fixed CSSHELP issue with getStyleAny

[TEE0207]

by modifying docs/css.md, packages/helpers/lib/index.ts and packages/tests/css-helper.test.ts"

Checklist:

• I have read freeCodeCamp's contribution guidelines.
• My pull request has a descriptive title (not a vague title like Update index.md)

Closes freeCodeCamp/freeCodeCamp#64218

[majestic-owl448]

is this PR related to an issue? Please link to the issue, or create one first to discuss the changes.

[TEE0207]

is this PR related to an issue? Please link to the issue, or create one first to discuss the changes.

Alright, yes it is... here's the link to the issue I fixed.
freeCodeCamp/freeCodeCamp#64218

[majestic-owl448]

please make sure the issue is linked in the appropriate place in the template

Closes #XXXXX

as the issue is in a different repository, use the whole link in place of #XXXXX

[majestic-owl448]

Thanks for the PR, but this approach is not the right fix for this issue.

getStyleAny is designed to accept a list of interchangeable selectors and return the style for whichever one the learner actually used. Requiring that ALL selectors in the list exist in the CSS breaks that contract: a learner who correctly uses one of the allowed selectors would have their solution rejected because the others aren't present.

The actual bug is in getStyle: when the CSS contains a rule with a universal selector (*), getStyle can match it against a query that doesn't use * (because some browsers normalize *:first-of-type to :first-of-type in selectorText). The fix should go in getStyle, checking whether the rule's selectorText contains a universal selector and skipping it when the queried selector does not.

Also, please link the issue properly in the PR template. Since the issue is in a different repository, use the full URL instead of #XXXXX:

Closes https://github.com/freeCodeCamp/freeCodeCamp/issues/64218