Why a rules file and not collocated with your components: → You can have one design system but different rules. Think a workspace with marketing site and a dashboard. You could allow `motion` classes on the marketing site but not the dashboard. → You can write rules for third-party components inside node_modules. Components you don't own. → One rule can cover many components. ^.*Content$ is every CardContent, DialogContent, AccordionContent. → You don't touch your existing code.