Newsletter sign-up form with success message - Using JS Regex

What are you most proud of, and what would you do differently next time?

Got to learn about the Regex in JavaScript, hoping it may help in the long term. Next time, I will be trying to use some 3rd party Apis of js for validation.

What challenges did you encounter, and how did you overcome them?

The most challenging part was to give styling to the input focus in a way that it fulfills the requirements. I got to know how multiple styling can be added through JS Object.assign() function, but the best way to do it was to just add or remove classes.

What specific areas of your project would you like help with?

Any Suggestions on how to get precise margins and paddings without spending hours on experimenting?