Order Summary Card Solution

Overall, I think you did a good job of matching the design, but there were a few minor things I noticed:

I would also practice using naming conventions that are easier to understand.

I would suggest working to clear your accessibility report. They should be pretty simple fix, like adding a <main> tag and switching your back slashes with forward slashes.

While "pixel-perfect" or whatever some people are promoting is not required, you still do want to get as close to the design as possible. Besides, the more accurate your code the more you improve. Specifically, the hover color on the Proceed to Payment button as well as the font seem to be off. The shadow behind the button wasn't added. Like I said, minor stuff. In the case that you were having any issues with those things, or if you'd like to provide feedback:

You can check out my solution here: https://www.frontendmentor.io/solutions/order-summary-component-using-flexbox-5UlxZi3Kt

FYI: I added an outline to my cancel button because when I was tabbing to it with my keyboard, I couldn't tell that my focus was there.