Intro Component with Sign-up Form using Sass

I coded desktop first, using Sass and flexbox layout.

It was great to practice how to validate Email using JavaScript.

-One question if you could help* I tried to gather all the inputs in the checkRequired function when input.value is empty, but I had to repeat it on the other functions, or it showed other error messages which was supposed to be shown only for the checkLength() or checkEmail(). If you could help to give me any suggestion on that, I would be happy☺️🙏

Any feedback & suggestion for improvement would be very much appreciated :)!!