How to hide the woo commerce shopping cart without disabling the plug-in

A conundrum. I need the plug-in because we’ve created product pages and if I disable the plug-in I can’t access/display the products (workshops). However, we don’t want to add prices at this time (maybe never) so we don’t want the shopping icon in the nav bar. The problem is – how to undisplay it, if that’s a word.

Have looked on line – none of their css codes work ;-(

Any suggestions?

Tried
#main-navigation li.nav-cart {
display: none;
}

Didn’t work – then I saw this for a child theme (mine’s a child theme)

#wpmenucartli {
display: none;
}

Nothing works!!!