DOC: Fix styles for dark mode in docs home

[datapythonista]

xref: #42744

We'll be making the pandas documentation have a dark mode soon. But some boxes in the docs home seem to have a white background, instead of a transparent one:

We should remove any custom style that is preventing the dark mode to work properly.

The changes can be tested against this branch to see if they work properly: #48285

[valanm22]

@datapythonista May I work on this issue?

[datapythonista]

@datapythonista May I work on this issue?

Sure, please do. Thanks @valanm22

[valanm22]

Do I replace the old svg images or do I upload them as new svg images?

[datapythonista]

Better replace the old images.

[valanm22]

Ok got it.

[thekavikumar]

I'll also try to fix it

[datapythonista]

Looks like the problem are not the svg images, but the styles. I updated the description.

[thekavikumar]

I'm not able to run python make.py HTML showing error module not found: No module named 'pandas._libs.interval
any solution?

[datapythonista]

In the project root run ./setup.py build_ext --inplace to compile pandas extensions, that should fix it. In the contributing documentation you have all the info.