Can't remove entry footer

I can’t, for the life of me, remove the entry footer in my site (the tags and categories).

When I inspect them with the chrome tool (F12) I can see something called: “Ul class=”post-categories”” But I can’t find “post-categories” ANYWHERE. Not in the style.css of my theme (Zerif lite) nor the bootstrap.css.

I’ve tried adding:

.post .entry-footer {
display:none !important;
}

But that won’t work.

Can anyone tell me how I find the information that I need with the F12 tool? Sometimes I seriously feel like I don’t get it. The “Tags” part is just covered in “p” and nothing else. It doesn’t have a class ID or anything as far as I can see.

If I want to edit the post image size, all I see is img{} and obviously I don’t want to change the image size of every image on my website…Some help with the F12 tool in general would be great.

Link to website.