Make Input disabled

Hello,
I have a Form with about 20 Fields, and a Function which determines User's access level, which is called at the beginning of Event. And I want to make some of Fields disabled for input (not dynamically but upon result of a Function). As with Semantic UI:

class="ui disabled input"

But, it looks like Fields' container classes are not parsed so I cannot just add something like "{var:class_disabled}" or "<?=$class_disabled ?>" to it.
Any ideas? Thanks.

OK my bad CC for some reason does in fact not parse it. If you need a form, you should instead create it in CF and then show in in your CC event using {chronoform:name}

BTW, CC lacks copying objects so much. I could easily avoid such problem by duplicating my complex Form with all its Fields, changing a bit, and showing different Forms to different users. Ugly but working. Well, just a suggestion.