Is it possible to hide the header without hurting seo?

Question

HTML

Hello.
There is no way to implement header.
I made a class for it with properties:

position: absolute;
  overflow: hidden;
  height: 1px;
  width: 1px;
  border: 0;

Will this negatively affect seo optimization and will such links be indexed at all?

Answer 1

What links to index?
To hide the header in general in parallel, hide without problems)