Update navbar, implement useNavbar hook, style updates

- Created a custom hook that returns an object with pages depending on user auth. This is a refactor of the logic found in the navbar component.
- Updated styles for card components
- Fix font size issues for mobile.
- Update theming to include a new pastel theme.

src/styles/globals.css

@@ -1,3 +1,7 @@
 @tailwind base;
 @tailwind components;
 @tailwind utilities;
+
+.card {
+    @apply shadow-md
+}