diff --git a/lib/project/app_pages/add_category.dart b/lib/project/app_pages/add_category.dart
index 12998a7..f928937 100644
--- a/lib/project/app_pages/add_category.dart
+++ b/lib/project/app_pages/add_category.dart
@@ -1,4 +1,3 @@
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_screenutil/flutter_screenutil.dart';
 import 'package:google_fonts/google_fonts.dart';
@@ -168,6 +167,7 @@ class _CategoryNameState extends State<CategoryName> {
                 return getTranslated(context, 'Category already exists');
               }
             }
+            return null;
           },
           decoration: InputDecoration(
               border: InputBorder.none,
diff --git a/lib/project/app_pages/analysis.dart b/lib/project/app_pages/analysis.dart
index 6d8e897..e594b9f 100644
--- a/lib/project/app_pages/analysis.dart
+++ b/lib/project/app_pages/analysis.dart
@@ -1,4 +1,3 @@
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_screenutil/flutter_screenutil.dart';
 import 'package:google_fonts/google_fonts.dart';
diff --git a/lib/project/app_pages/calendar.dart b/lib/project/app_pages/calendar.dart
index 7a18c6e..f424008 100644
--- a/lib/project/app_pages/calendar.dart
+++ b/lib/project/app_pages/calendar.dart
@@ -1,6 +1,5 @@
 import 'dart:collection';
 
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_screenutil/flutter_screenutil.dart';
 import 'package:flutter_swipe_action_cell/core/cell.dart';
@@ -18,7 +17,6 @@ import 'package:money_assistant_2608/project/localization/methods.dart';
 import 'package:table_calendar/table_calendar.dart';
 import 'dart:io' show Platform;
 
-import '../classes/input_model.dart';
 import 'edit.dart';
 
 class Calendar extends StatelessWidget {
@@ -372,6 +370,7 @@ class _CalendarBodyState extends State<CalendarBody> {
                       child: _buildEventsMarker(date, events),
                     );
                   }
+                  return null;
                 },
               ),
 
diff --git a/lib/project/app_pages/edit.dart b/lib/project/app_pages/edit.dart
index 24d7d4d..fe9401d 100644
--- a/lib/project/app_pages/edit.dart
+++ b/lib/project/app_pages/edit.dart
@@ -1,4 +1,3 @@
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:money_assistant_2608/project/classes/app_bar.dart';
 import 'package:money_assistant_2608/project/classes/constants.dart';
diff --git a/lib/project/app_pages/edit_expense_category.dart b/lib/project/app_pages/edit_expense_category.dart
index d45edba..492a4a6 100644
--- a/lib/project/app_pages/edit_expense_category.dart
+++ b/lib/project/app_pages/edit_expense_category.dart
@@ -1,4 +1,3 @@
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:money_assistant_2608/project/classes/app_bar.dart';
 import 'package:money_assistant_2608/project/classes/constants.dart';
diff --git a/lib/project/app_pages/edit_income_category.dart b/lib/project/app_pages/edit_income_category.dart
index e7139b4..244f9cb 100644
--- a/lib/project/app_pages/edit_income_category.dart
+++ b/lib/project/app_pages/edit_income_category.dart
@@ -1,4 +1,3 @@
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:money_assistant_2608'
     '/project/classes/app_bar.dart';
diff --git a/lib/project/app_pages/expense_category.dart b/lib/project/app_pages/expense_category.dart
index c8ce78f..6da1a3e 100644
--- a/lib/project/app_pages/expense_category.dart
+++ b/lib/project/app_pages/expense_category.dart
@@ -1,4 +1,3 @@
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_screenutil/flutter_screenutil.dart';
 import 'package:money_assistant_2608/project/classes/app_bar.dart';
diff --git a/lib/project/app_pages/income_category.dart b/lib/project/app_pages/income_category.dart
index 03ba8ce..328d408 100644
--- a/lib/project/app_pages/income_category.dart
+++ b/lib/project/app_pages/income_category.dart
@@ -1,4 +1,3 @@
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_screenutil/flutter_screenutil.dart';
 import 'package:money_assistant_2608/project/classes/app_bar.dart';
diff --git a/lib/project/app_pages/input.dart b/lib/project/app_pages/input.dart
index 035d3d9..4de2310 100644
--- a/lib/project/app_pages/input.dart
+++ b/lib/project/app_pages/input.dart
@@ -1,9 +1,7 @@
 import 'dart:core';
 import 'dart:io' show Platform;
 import 'package:day_night_time_picker/day_night_time_picker.dart';
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
-import 'package:flutter/services.dart';
 import 'package:flutter_material_pickers/flutter_material_pickers.dart';
 import 'package:flutter_screenutil/flutter_screenutil.dart';
 import 'package:google_fonts/google_fonts.dart';
diff --git a/lib/project/app_pages/others.dart b/lib/project/app_pages/others.dart
index 7df1e53..3426dd2 100644
--- a/lib/project/app_pages/others.dart
+++ b/lib/project/app_pages/others.dart
@@ -1,6 +1,5 @@
 import 'dart:core';
 
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_screenutil/flutter_screenutil.dart';
 import 'package:font_awesome_flutter/font_awesome_flutter.dart';
@@ -41,7 +40,7 @@ class Other extends StatelessWidget {
                   CircleAvatar(
                     child: CircleAvatar(
                         child: Icon(
-                          FontAwesomeIcons.smileBeam,
+                          FontAwesomeIcons.faceSmileBeam,
                           color: Colors.black,
                           size: 71.sp,
                         ),
diff --git a/lib/project/app_pages/select_date_format.dart b/lib/project/app_pages/select_date_format.dart
index 22ff996..af6b511 100644
--- a/lib/project/app_pages/select_date_format.dart
+++ b/lib/project/app_pages/select_date_format.dart
@@ -1,4 +1,3 @@
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:intl/intl.dart';
 import 'package:money_assistant_2608/project/classes/constants.dart';
diff --git a/lib/project/app_pages/select_icon.dart b/lib/project/app_pages/select_icon.dart
index 6ae3094..8bb1bc5 100644
--- a/lib/project/app_pages/select_icon.dart
+++ b/lib/project/app_pages/select_icon.dart
@@ -1,4 +1,3 @@
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_screenutil/flutter_screenutil.dart';
 import 'package:money_assistant_2608/project/classes/app_bar.dart';
diff --git a/lib/project/auth_pages/sign_in.dart b/lib/project/auth_pages/sign_in.dart
index 4ffeb35..c182fd4 100644
--- a/lib/project/auth_pages/sign_in.dart
+++ b/lib/project/auth_pages/sign_in.dart
@@ -1,4 +1,3 @@
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_login/flutter_login.dart';
 import 'package:font_awesome_flutter/font_awesome_flutter.dart';
diff --git a/lib/project/auth_pages/user_account.dart b/lib/project/auth_pages/user_account.dart
index fb03fc7..984ff60 100644
--- a/lib/project/auth_pages/user_account.dart
+++ b/lib/project/auth_pages/user_account.dart
@@ -1,4 +1,3 @@
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_screenutil/flutter_screenutil.dart';
 import 'package:money_assistant_2608/project/classes/constants.dart';
diff --git a/lib/project/classes/app_bar.dart b/lib/project/classes/app_bar.dart
index 608f8cf..a9143e2 100644
--- a/lib/project/classes/app_bar.dart
+++ b/lib/project/classes/app_bar.dart
@@ -1,4 +1,3 @@
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:money_assistant_2608/project/localization/methods.dart';
 import 'package:flutter_screenutil/flutter_screenutil.dart';
diff --git a/lib/project/classes/chart_pie.dart b/lib/project/classes/chart_pie.dart
index 13c9ddd..8be8f9e 100644
--- a/lib/project/classes/chart_pie.dart
+++ b/lib/project/classes/chart_pie.dart
@@ -1,4 +1,3 @@
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_screenutil/flutter_screenutil.dart';
 import 'package:money_assistant_2608/project/localization/methods.dart';
diff --git a/lib/project/classes/constants.dart b/lib/project/classes/constants.dart
index 6906a69..2da7a5d 100644
--- a/lib/project/classes/constants.dart
+++ b/lib/project/classes/constants.dart
@@ -101,6 +101,7 @@ Widget? connectionUI(AsyncSnapshot<List<InputModel>> snapshot) {
       child: CircularProgressIndicator(),
     );
   }
+  return null;
 }
 
 List<CategoryItem> createItemList({
diff --git a/lib/project/classes/custom_toast.dart b/lib/project/classes/custom_toast.dart
index e81f4dd..559bcf2 100644
--- a/lib/project/classes/custom_toast.dart
+++ b/lib/project/classes/custom_toast.dart
@@ -1,4 +1,3 @@
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:fluttertoast/fluttertoast.dart';
 import 'package:money_assistant_2608/project/classes/constants.dart';
diff --git a/lib/project/classes/dropdown_box.dart b/lib/project/classes/dropdown_box.dart
index a4aae6e..5fd7870 100644
--- a/lib/project/classes/dropdown_box.dart
+++ b/lib/project/classes/dropdown_box.dart
@@ -1,7 +1,5 @@
-import 'dart:ui';
 import 'package:provider/provider.dart';
 
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:money_assistant_2608/project/database_management/shared_preferences_services.dart';
 import 'package:money_assistant_2608/project/localization/methods.dart';
diff --git a/lib/project/classes/keyboard.dart b/lib/project/classes/keyboard.dart
index 7351284..96e9ed7 100644
--- a/lib/project/classes/keyboard.dart
+++ b/lib/project/classes/keyboard.dart
@@ -1,4 +1,3 @@
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_screenutil/flutter_screenutil.dart';
 import 'package:money_assistant_2608/project/classes/constants.dart';
diff --git a/lib/project/classes/lockscreen.dart b/lib/project/classes/lockscreen.dart
index fbbd769..bb417b1 100644
--- a/lib/project/classes/lockscreen.dart
+++ b/lib/project/classes/lockscreen.dart
@@ -1,4 +1,3 @@
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_app_lock/flutter_app_lock.dart';
 import 'package:flutter_screen_lock/configurations/input_button_config.dart';
diff --git a/lib/project/classes/saveOrSaveAndDeleteButtons.dart b/lib/project/classes/saveOrSaveAndDeleteButtons.dart
index f849c9d..555938a 100644
--- a/lib/project/classes/saveOrSaveAndDeleteButtons.dart
+++ b/lib/project/classes/saveOrSaveAndDeleteButtons.dart
@@ -1,5 +1,4 @@
 import 'dart:io' show Platform;
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_screenutil/flutter_screenutil.dart';
 import 'package:money_assistant_2608/project/classes/alert_dialog.dart';
@@ -36,10 +35,7 @@ class _SaveButtonState extends State<SaveButton> {
           }
         },
         style: ElevatedButton.styleFrom(
-          padding: EdgeInsets.symmetric(vertical: 10.h, horizontal: 20.w),
-          primary: Color.fromRGBO(236, 158, 66, 1),
-          onPrimary: white,
-          onSurface: grey,
+          foregroundColor: white, backgroundColor: Color.fromRGBO(236, 158, 66, 1), padding: EdgeInsets.symmetric(vertical: 10.h, horizontal: 20.w), disabledForegroundColor: grey.withOpacity(0.38), disabledBackgroundColor: grey.withOpacity(0.12),
           elevation: 10,
           shape: RoundedRectangleBorder(
             borderRadius: BorderRadius.circular(18.0.r),
@@ -100,10 +96,7 @@ class SaveAndDeleteButton extends StatelessWidget {
               }
             },
             style: ElevatedButton.styleFrom(
-                padding: EdgeInsets.symmetric(vertical: 10.h, horizontal: 20.w),
-                primary: white,
-                onPrimary: red,
-                onSurface: grey,
+                foregroundColor: red, backgroundColor: white, padding: EdgeInsets.symmetric(vertical: 10.h, horizontal: 20.w), disabledForegroundColor: grey.withOpacity(0.38), disabledBackgroundColor: grey.withOpacity(0.12),
                 side: BorderSide(
                   color: red,
                   width: 2.h,
diff --git a/lib/project/database_management/shared_preferences_services.dart b/lib/project/database_management/shared_preferences_services.dart
index 0148868..a9a0900 100644
--- a/lib/project/database_management/shared_preferences_services.dart
+++ b/lib/project/database_management/shared_preferences_services.dart
@@ -1,8 +1,6 @@
 import 'dart:convert';
 import 'dart:io';
-import 'dart:ui';
 
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_boxicons/flutter_boxicons.dart';
 import 'package:font_awesome_flutter/font_awesome_flutter.dart';
diff --git a/lib/project/home.dart b/lib/project/home.dart
index d1af355..d423a11 100644
--- a/lib/project/home.dart
+++ b/lib/project/home.dart
@@ -1,7 +1,4 @@
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
-import 'package:flutter/painting.dart';
-import 'package:flutter/rendering.dart';
 import 'package:flutter_screenutil/flutter_screenutil.dart';
 import 'package:money_assistant_2608/project/classes/constants.dart';
 import 'package:money_assistant_2608/project/database_management/sqflite_services.dart';
@@ -52,7 +49,7 @@ class _HomeState extends State<Home> {
       appStoreIdentifier: '1582638369',
     );
 
-    WidgetsBinding.instance?.addPostFrameCallback((_) async {
+    WidgetsBinding.instance.addPostFrameCallback((_) async {
 
       await rateMyApp.init();
       rateMyApp.conditions.forEach((condition) {
diff --git a/lib/project/real_main.dart b/lib/project/real_main.dart
index d8c229f..f15f080 100644
--- a/lib/project/real_main.dart
+++ b/lib/project/real_main.dart
@@ -1,11 +1,9 @@
-import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_localizations/flutter_localizations.dart';
 import 'package:flutter_screenutil/flutter_screenutil.dart';
 import 'package:money_assistant_2608/project/auth_pages/sign_in.dart';
 import 'database_management/shared_preferences_services.dart';
 import 'localization/app_localization.dart';
-import 'home.dart';
 
 void realMain() async {
   WidgetsFlutterBinding.ensureInitialized();
@@ -65,16 +63,16 @@ class _MyAppState extends State<MyApp> {
           debugShowCheckedModeBanner: false,
           theme: ThemeData(
             textTheme: TextTheme(
-              headline3: TextStyle(
+              displaySmall: TextStyle(
                 fontFamily: 'OpenSans',
                 fontSize: 45.0,
                 color: Colors.deepOrangeAccent,
               ),
-              button: TextStyle(
+              labelLarge: TextStyle(
                 fontFamily: 'OpenSans',
               ),
-              subtitle1: TextStyle(fontFamily: 'NotoSans'),
-              bodyText2: TextStyle(fontFamily: 'NotoSans'),
+              titleMedium: TextStyle(fontFamily: 'NotoSans'),
+              bodyMedium: TextStyle(fontFamily: 'NotoSans'),
             ),
             colorScheme: ColorScheme.fromSwatch(primarySwatch: Colors.indigo)
                 .copyWith(secondary: Colors.orange),
@@ -82,7 +80,7 @@ class _MyAppState extends State<MyApp> {
                 TextSelectionThemeData(cursorColor: Colors.amberAccent),
           ),
           builder: (context, widget) => MediaQuery(
-            data: MediaQuery.of(context).copyWith(textScaleFactor: 1),
+            data: MediaQuery.of(context).copyWith(textScaler: TextScaler.linear(1)),
             child: widget!,
           ),
           home: SignIn(),