Hey again John,
I double checked on my sandbox site just to make sure and the following CSS does work, it removes only “Zerif Lite powered by WordPress” part.
Where exactly are you adding the code? The reason I ask is because I’m not being able to see it when inspecting your site which means either the there is something wrong with the CSS code above this or you’re not adding it to the right place.
.zerif-copyright-box {
display: none;
}
As for what Eirik suggested, while this can be done this is definitely not the proper way of doing things. First of all editing php files via WordPress editor is not a good thing and in many cases can result in fatal errors, you’d want to use proper text editor (Notepad++, Sublime etc). Aside from that editing theme files should be done only in child theme as you don’t want to lose the changes every time you update the theme.
As this should be possible with just CSS I’d suggest using CSS as it is much easier.
Best regards,
Bojan