Trouble styling Wysija newsletter

Hello!

I’m admin for the site BAVoice, and I was asked to add a Newsletter feature to the site. I ended up choosing Wysija, since it was so recommended, but I’m having trouble styling it.

This page shows the already up-and-running Wysija plugin, but I’m also trying to add it to the frontpage. If you check the frontpage, you’ll find a grey box with a text input field and a black subscribe button.

Here’s the thing: I am totally stumped as to how to integrate Wysija into this already existing design. I need it to look exactly like it does now, but have no idea how to proceed (I’m very bad at CSS). I don’t care if it’s an iframe, PHP or HTML, I just need it to work.

Any pointers?