Hide featured image

Hi there!

I’m having a bit of a problem in getting rid of the featured image. I need it for the overview (https://jeniferfriedmann.de/arbeitsproben/) but I don’t want it to show on the post page. The only thing I managed so far is to make the image a bit smaller which is a step in the right direction but not really the goal.

Is there a CSS code I can add to get rid of the image? That would be pretty great. I’m totally clueless when it comes to coding so I’ll appreciate every help 🙂

The page I need help with: [log in to see the link]