- introduce central pet age utilities (calculate, format, birthday check)
- replace static pet.age with dynamic birthDate logic
- display growing age correctly in pet detail view
- prepare foundation for birthday highlights and notifications
- fix duplicate imports and ensure stable build
- add disabled and loading states for all buttons
- align danger button radius and interaction with design system
- improve native select styling for consistent rounded appearance
- normalize focus, hover and active states for form controls
- ensure visual consistency across pets, posts and forms
- fix post preview modal height and scrolling (comments fully visible)
- prevent bottom navigation from overlapping modal content
- cleanup duplicate global CSS definitions
- normalize spacing and overflow behavior across feed and explore
- improve overall layout stability on mobile devices
- introduce global design system via CSS variables
- modern green-based color palette with improved readability
- unify Feed, Explore and Profile visual language
- add discovery posts visual highlight via border (no text shift)
- improve card depth, shadows and container consistency
- stabilize personalized feed logic (subscriptions + discovery)
- prepare UI for future theming without TSX changes