b2 user manual isn't readable

[sdarwin]

https://www.boost.org/doc/libs/1_89_0/tools/build/doc/html/index.html

compare to

https://original.boost.org/doc/libs/1_89_0/tools/build/doc/html/index.html

exbigboss writes, in the boost slack channel:

That background: black; shouldn't be there
4:29
It seems just literally removing that fixes it in both light and dark modes
4:29

[grafikrobot]

Compared to.. https://www.bfgroup.xyz/b2/manual/release/index.html