Different layout on smaller (smartphone) resolution

Hey guys. I’m stuck on this one, would really appreciate if someone could assist.

Want to have two different layouts of the contact form 7. One on bigger, PC screen resolution where some text would be on one (left) side and the form on other (rights) side. But can’t get it to work well on smartphones so would like to have a different layout there – the text would be on top and the form below the text. How can I do this?

Thanks in advance!

https://www.ads-software.com/plugins/contact-form-7/