Hi Fraser,
Great job on this one!
Looking at the preview above it looks like you need to set a narrower max width on the content so it doesn't spread quite so wide. Other than that, design all looks spot on to me.
I'm not sure what you mean about the footer as you don't seem to have one in your html? Have you tried making the body a flex column and setting the main to flex-grow 1? That would push the footer down when you have one. Or grid is an option
I can see you've removed the alt attributes completely from the star images. They are still needed on there but should be left empty like alt=""
. As voiceover will still announce svg images despite the empty alt tag (annoyingly!) it's best to also add aria-hidden="true" to those svgs.
I wouldn't do the stars with background images as suggested above by the way. In a real project they would be added to the html programmatically and that's unlikely to be done with background images.
Another alt related suggestion is to not say things like "picture of" in alt descriptions. That is already an image tag, so just the persons name will be a fine description.
Take a look again at what the section element is for. I would make this whole challenge one section, as it's all related to "why users love the products". You could make the bottom 3 testimonials into their own section, but if you did that you'd need to add a visually hidden heading to the section.
I hope these pointers are useful. Keep going, you're doing really well π