How do Gas Fees for "Offers" Work?

Today I was excited to notice I received my first offers on a couple pieces I had made about a week ago. They weren't huge, but they're fine for trying to start getting my stuff out there. To my dismay, when I went to accept the offer, I noticed I had to pay gas, which ironically was more than I'd make on selling the items. Is gas not paid for by the buyer? I tried digging around for more info on this, but couldn't find any in the opensea FAQ or other sites with information.

Do both the buyer and seller have to pay gas? I assumed solely the buyer paid gas fees. Is it just this way if it is specifically a unique offer that you are accepting?