Unable to make changes to CSS in a correct way

Hello,
I hope there is someone that can help me out… I’m really lost how to do the changes in the CSS to get the plug-in to look as I like it on my website. Believe me – I have tried to work it out by exploring the support forum and try to do the things suggested to others.
But I don’t understand. So please help me out.

The plug-in is seen as the second footer on my website
and I just want it to look as First and Third footer.

I’m not good at CSS so please give the information in a very “basic” way. Thank you in advance.

https://www.ads-software.com/plugins/recent-posts-widget-extended/