What is better to use when adapting: flex-basis or width?

Question

css

Hello! I'm trying to type on flex, but I don't quite understand the difference between flex-basis (the main axis is horizontal) and width? I looked at examples, and they do it this way and that + if they write flex-basis, then they also add max-width. So, what should be applied and changed accordingly in media queries when layout on
flex: flex-basis or width ?

Answer 1

Take a look here: frontend.aliterax.com/newton/card.html

Answer 2

Take jquery, write. The clickable search field changes its width, and for social media buttons, just hide();