Targeting Blog Page CSS class without using #blocknumbers

Site URL: https://pelican-chiton-xwy4.squarespace.com/blog/apocapoc-chef-interview

Hello,

I'm working on Blog pages using custom CSS's and I'd like to target some of the elements I've created by "class" instead of having to do it by targeting "#blocknumbers", since the latest keep on changing on every new Blog page forcing me to update the CSS's everytime I create a new one.

For example, if I want to target specifically the latest image on the page I can only seem to do it by using its #blocknumber, because if I use "img.thumb-image.loaded" it affects a bunch more images where I don't want any change to be applied.

Any tips on how could I target a specific element on the Blog page, like a single image or paragraph, without having to use its #blocknumber?

Thanks!