Issue with the 2021 css chapter

[Stanisław Gregor]

In the fragment

While CSS-in-JS adoption grew to 3% of all pages crawled (a 1% jump from last year) [...]

you probably meant a growth by 1 percentage point, instead of growth by 1%. It's different.

[Shuvam Manna]

Thanks for floating this up @staszek998
Issued a patch.