Reduce the use of helper CSS classes

[astraloverflow]

We currently use the RSCSS CSS style/structure guide (enforced through stylelint). And as it stands, there are too many helper classes in use throughout the website.

https://github.com/uTox/website/blob/e2eaf57190186c586694b630141f88bad2e2562f/src/styles/_helpers.scss

Which RSCSS Recommends using as few a possible.

http://rscss.io/helpers.html

using too many helpers should be discouraged

it's very preferrable to keep your number of helpers to a minimum