Remove space below post in Twenty Twelve

Hello agne987,

You’ll want to make a child theme first (see how here: https://codex.www.ads-software.com/Child_Themes )

Then add this line of code to your child themes style.css:

.site-content article {
     margin-bottom: 2rem;
}

You can adjust the value “2rem” to whatever you want.

Thanks for you’r help but it didn’t help. I could see no difference when adding the code you suggested to my child theme.

.site-content article {
	border-bottom: none;
	border-bottom: 0.01rem;
}

Is there another class I should adjust?

Your code has border-bottom, try margin-bottom instead.