Dark theme

lib/src/app.dart

@@ -1,15 +1,20 @@
 import 'package:flutter/material.dart';
 import 'package:quickgui/src/pages/main_page.dart';
 
-class App extends StatelessWidget {
+class App extends StatefulWidget {
   const App({Key? key}) : super(key: key);
 
+  @override
+  State<App> createState() => _AppState();
+}
+
+class _AppState extends State<App> {
   @override
   Widget build(BuildContext context) {
     return MaterialApp(
-        theme: ThemeData(
+      theme: ThemeData(primarySwatch: Colors.pink),
-          primarySwatch: Colors.pink,
+      darkTheme: ThemeData.dark(),
-        ),
+      home: const MainPage(title: 'Quickgui - A Flutter frontend for Quickget and Quickemu'),
-        home: const MainPage(title: 'Quickgui - A Flutter frontend for Quickget and Quickemu'));
+    );
   }
 }

lib/src/widgets/downloader/cancel_dismiss_button.dart

@@ -18,6 +18,9 @@ class CancelDismissButton extends StatelessWidget {
         mainAxisAlignment: MainAxisAlignment.center,
         children: [
           ElevatedButton(
+            style: ElevatedButton.styleFrom(
+              primary: Theme.of(context).colorScheme.surface,
+            ),
             onPressed: !downloadFinished
                 ? onCancel
                 : () {

lib/src/widgets/home_page/downloader_menu.dart

@@ -29,7 +29,7 @@ class _DownloaderMenuState extends State<DownloaderMenu> with PreferencesMixin {
   Widget build(BuildContext context) {
     return Expanded(
       child: Container(
-        color: Colors.pink,
+        color: Theme.of(context).brightness == Brightness.dark ? Theme.of(context).colorScheme.surface : Theme.of(context).colorScheme.primary,
         child: Column(
           children: [
             Row(

lib/src/widgets/home_page/home_page_button.dart

@@ -32,8 +32,8 @@ class HomePageButton extends StatelessWidget {
             ),
             ElevatedButton(
               style: ElevatedButton.styleFrom(
-                primary: Colors.white,
+                primary: Theme.of(context).canvasColor, //Theme.of(context).canvasColor
-                onPrimary: Colors.pink,
+                onPrimary: Theme.of(context).brightness == Brightness.dark ? Colors.white70 : Theme.of(context).colorScheme.primary,
               ),
               onPressed: onPressed,
               child: Padding(

lib/src/widgets/home_page/main_menu.dart

@@ -10,7 +10,7 @@ class MainMenu extends StatelessWidget {
   Widget build(BuildContext context) {
     return Expanded(
       child: Container(
-        color: Colors.pink,
+        color: Theme.of(context).brightness == Brightness.dark ? Theme.of(context).colorScheme.surface : Theme.of(context).colorScheme.primary,
         child: Padding(
           padding: const EdgeInsets.all(8.0),
           child: Row(