Login dialogue in header

Hello,
I am right now creating a WordPress Site where users have the possibility to log in. Everything is working fine, but I want the login to be more easy.
It should be something like this:

should be like this

So just a login dialogue in the header.

What I am able to accomplish is this:

View post on imgur.com

But its pretty ugly.
I would like best if the login dialogue is on the right side of my top-menu.
Anyone knows how I can do this?
I am using a child theme of 2017 theme.

Thank you for your help