Refactor and update navigation and constants

- Refactor code for consistency in formatting and styling.
- Update `navLinks` to revise URLs and labels for improved clarity.
- Adjust button text in `DesktopNav` from "Portal" to "Kontakt".

constant/Constant.ts

@@ -11,7 +11,7 @@ export const navLinks = [
     },
     {
         id: 3,
-        url: 'contact',
-        label: 'Kontakt',
+        url: 'services',
+        label: 'Leistungen',
     }
 ];