Theme is Forcing Gleam.io Container to Full Content Area Size

So this is a really weird issue that I’m having:

I am attempting to embed a gleam.io giveaway into one of my WordPress posts, and the embedded widget itself is being forced to full-width.

Here is what I am talking about in action: https://www.jotaku.net/2018/02/06/jotaku-network-relaunch-giveaway/
Here is an example of how it is supposed to function once embedded: https://www.jlist.com/blog/contest/megumis-valentines-day-contest/

Any ideas on how I can fix this? I was previously having similar issues with images that have captions, but some other advice here on the forums solved that problem. It didn’t work in this case though.

Thanks!

Thank you very much! That topic solved my problem!