$navclass use

[NoPretender]

I'm moving two custom pages and using USERCP_SHELL to incorporate the pages into the User CP. When I view the pages $navclass is basically non-existant and the menu is black (custom style). What am I forgetting to include/missing to get $navclass to display in the menu? I'm just using alt2 for the custom links in the menu so that's fine, but how do I include the navclass variable?

Thanks for your help. I'm assuming it's easy, but can't find it.