Reply To: WPs CSS settings in a WP site merged with another CMS system (genealogy)

[Atelierbram]

Now, my problem is that WP seems to somehow block the CSS settings for my TNG site. I have added the CSS code to the custom CSS part in my WP, but it didn’t help.

This CSS is included, the problem is the classnames used in that CSS don’t match up with the tags in your WordPress themes, in other words the aren’t hitting any targets.
For example for the background of body it is targeting the .publicbody classname which simply isn’t set on the body-tag in your new WP theme. Now in your CSS if you would change .publicbody { to just body { you will see the background-image appear. Same for any other element on the page. Another example, there are styles associated with the main content area .cb-tng-area in your custom stylesheet, also not to be found in your new theme, but if you would rename that one to .inner-wrapper which takes the same place in the layout that would work.
Do you use (Chrome)Developer Tools or Firebug to “inspect element”?