Updates dashboard UI and improves styling

Improves the dashboard's appearance and user experience by updating styles and layouts.

Changes include:
- Updates to color schemes and spacing for better readability and visual appeal.
- Implements a responsive layout for the header to adapt to different screen sizes.
- Refactors button styles for consistency and clarity.
- Adds a gradient background to the main dashboard page.
- Updates the NextAuth URL in the development environment.

package.json

@@ -36,8 +36,7 @@
     "react": "^19.1.0",
     "react-chartjs-2": "^5.0.0",
     "react-dom": "^19.1.0",
-    "react-leaflet": "^5.0.0",
-    "tailwindcss": "^4.1.7"
+    "react-leaflet": "^5.0.0"
   },
   "devDependencies": {
     "@eslint/eslintrc": "^3.3.1",
@@ -50,13 +49,13 @@
     "@types/react-dom": "^19.1.5",
     "@typescript-eslint/eslint-plugin": "^8.32.1",
     "@typescript-eslint/parser": "^8.32.1",
-    "autoprefixer": "^10.4.0",
     "eslint": "^9.27.0",
     "eslint-config-next": "^15.3.2",
     "eslint-plugin-prettier": "^5.4.0",
-    "postcss": "^8.4.0",
+    "postcss": "^8.5.3",
     "prettier": "^3.5.3",
     "prisma": "^6.8.2",
+    "tailwindcss": "^4.1.7",
     "typescript": "^5.0.0"
   }
 }