Responsive mobile first workflow with Flexbox, CSS grid & Vanilla JS

This is the third premium challenge I have attempted on Frontend Mentor.
I thought I might use this template as a temporary portfolio for my work so that is why I decided to do this challenge. There are definitely areas to improve on and I feel that my CSS might be a bit bloated in some areas. One other thing I still need to work on is making custom messages for forms when the fields have not been filled out correctly. I do not know much about form validation, so this is something I will look at before starting the next project and hopefully update on this project in the future.