I am unable to center elements that will be a list of blog posts going forward. The Postlist element is loaded into my App.js file. I was able to center the nav bar using the technique mentioned

While looking at your code and what is mentioned you should consider D.R.Y. when writing components, example:

const PostList = (props) => (
  <div className='blog-list-container'>
    <Router>
      {posts.map((post) => {
        return (
          <Link key={post.id} to={post.link} className='blog-element'>
            {post.name}
          </Link>
        )
      })}
    </Router>
  </div>
)

export default PostList