3 colums in 1 row when shown on phone?

Hey!
I’ve been looking for an answer to this for quite a while now and I finally decided to just create a post. I’m making a personal website as a part of an exam and one requirement is that it has to be responsive. My problem is that when I create 3 columns in a single row on one of my pages ex -> http://katrinegregersen.dk/?page_id=43 it only shows one column at the time when I load it on my phone thus removing the purpose of the “timeline” I created in photoshop.

Is there any way you can fix it so it shows all 3 columns even when having the website on a phone?

I know the basics of CSS if that is beneficial in any way. :)

Thanks!

Theme: Optimizer
Katrine
Denmark