How to make blocks with the same size?

Question

WordPress

Hello. The first link is a demo of my site's theme. There are blocks with the same size (height), that is, even if the title is two-line or a different number of letters in the content, the blocks adapt to the large block. The second link is my test site. But there blocks with different sizes. I inspected the code, it seems to be the same, there is no flex. What do i do?

https://demo.mysterythemes.com/color-blog

https://dizak.uz