I have been searching the support forum and how found many examples of sites which integrate WP and discourse like this: https://community.namati.org/
However, please excuse my lack of understanding, I cannot see how to do this on my own. Does this have to be specifically integrated per wordpress theme, or is there some generic code I can put in a special wordpress page which then shows discourse after the wordpress header on my page?
I am not sure if the css option you provided does exactly what I am looking for though. To maybe make my explanation clearer I will provide visual examples below. To be able to do this, I guess there needs to be some custom code in the wordpress theme?
Wordpress landing home page:
Wordpress page, with discourse forum below header:
If you are talking about embedding Discourse into your wordpress site I would advise against that. Plus I am pretty sure its not supported. Instead simply have that forum link go to your discourse site and then add code into the customization > CSS/HTML > Header section like @ccdw shows to make it look like your wordpress site. That is what the site you initially reference does.