Call to action button in nav bar

Is it possible to add a call to action button to the header? I would like to have something which i permanently in view. I appreciate this might not be possible at certain view ports.

You could add the .welcome-button class to one of your menu items, then work on it from there to adapt it for menu display.
Or you could target a menu item by ID and style it as you like.
There are more ways of doing this.