Responsive landing page using SASS, Grid and Flexbox

I found this the hardest of the newbie challenges so far - I rebuilt it at least 3 times using different techniques! Obviously I would be grateful for any feedback on improvements I could make. One thing I'm struggling with is trying to use clamp() for font-size. I tried using it in my code but at times it was making the font-size a wildly different size than the design, so I took it out. Does anyone have any advice or good resources that you used to understand clamp() for font-sizing? I have managed to use clamp() for width, it's just font-sizing that is giving me some trouble!

Thanks!