Order Summary complete(ish)

Welp, this is my first ever attempt at anything like this so I hope I got close enough for an absolute beginner. I already know my code is a mess but I definitely struggled with making the summary responsive and keeping it looking how it's supposed to. So if anyone could show me the way, I'd appreciate it. And any other pointers they'd like to tell me, I'm good with constructive criticism. Here's to building a new skill!