Problem with look of the site with multilang

Hello,

I am experiencing a problem with my wordpress site.
The problem is as follows:
I need to make my site into multilingual site, I have installed plugins and things like that but I still have a problem.
For example when I click on the other language extension then the layout of the site is all messed up and CSS that I wrote for the main site will not apply on the other sites.
Can anyone help me out with this?

My site is : http://www.alfa-kem.fi
You can take a look at yourself and see what I mean by “messed up”.