Hiding thumbnail of special post ID in bloglist

I created a nice website
[ redundant link removed ]
for my tennis club using the theme twenty sixteen. On the starting page (here page ID=40) there are arranged 4 thumbnails linked to the most actual themes, followed by the blog list using the ?content views“ plugin (pt-cv-view ID=0e7aab3kcx).

As an additional feature I want to hide the thumbnail of one special post (here post ID=14515, the post width an animated gif) on horizontal screens of tablets or on PC screens (displaying widgets on the right side) using css code. The @media function for this screen selection is working well – as example I built in black borders for smartphones and red borders for wide screens (just open the website and turn a tablet 90 degrees).

I tried a variety of css codes using

@media screen and (min-width:55.875em) .post-14515 or .postid-14515 .pt-cv-thumbnail {display: none !important;}

or similar but I didn’t succeed to hide this special post.

What is the correct css code for hiding this special post?

Thanks for your help

• This topic was modified 2 years ago by Jan Dembowski. Reason: Moved to Fixing WordPress, this is not an Developing with WordPress topic

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