Order Summary Card - HTML, CSS, Flexbox

Hi! I'd be grateful to know if my code is as clean and elegant as it could be, and if there's a better way to accomplish things than what I came up with.

The only real issue I was conscious of that I wasn't able to fix is that the background-image simply would not show up on my broswer. I even downloaded someone else's attempt of this challenge, whose preview had the background showing - and despite being present in their code as well - the background-image would not display when I ran, viewed, Chrome Dev Tools inspected etc. the .html myself. Why's that happening? I'm on the latest version of Chrome.

Any comments, insights, suggestions, and advice is appreciated. Thank you!