design: Better paddings in tablet mode

lib/pages/chat_members/chat_members_view.dart

@@ -53,6 +53,7 @@ class ChatMembersView extends StatelessWidget {
       ),
       body: MaxWidthBody(
         withScrolling: false,
+        innerPadding: const EdgeInsets.symmetric(vertical: 8),
         child: error != null
             ? Center(
                 child: Padding(

lib/pages/invitation_selection/invitation_selection_view.dart

@@ -36,6 +36,7 @@ class InvitationSelectionView extends StatelessWidget {
         title: Text(L10n.of(context)!.inviteContact),
       ),
       body: MaxWidthBody(
+        innerPadding: const EdgeInsets.symmetric(vertical: 8),
         child: Column(
           children: [
             Padding(

lib/pages/new_private_chat/new_private_chat_view.dart

@@ -39,6 +39,7 @@ class NewPrivateChatView extends StatelessWidget {
       ),
       body: MaxWidthBody(
         withScrolling: false,
+        innerPadding: const EdgeInsets.symmetric(vertical: 8),
         child: Column(
           children: [
             Padding(
@@ -151,6 +152,8 @@ class NewPrivateChatView extends StatelessWidget {
                     Center(
                       child: Padding(
                         padding: const EdgeInsets.all(64.0),
+                        child: ConstrainedBox(
+                          constraints: const BoxConstraints(maxHeight: 256),
                           child: Material(
                             borderRadius: BorderRadius.circular(12),
                             elevation: 10,
@@ -167,6 +170,7 @@ class NewPrivateChatView extends StatelessWidget {
                           ),
                         ),
                       ),
+                    ),
                   ],
                 ),
                 secondChild: FutureBuilder(

lib/widgets/layouts/max_width_body.dart

@@ -9,12 +9,14 @@ class MaxWidthBody extends StatelessWidget {
   final double maxWidth;
   final bool withFrame;
   final bool withScrolling;
+  final EdgeInsets? innerPadding;
 
   const MaxWidthBody({
     this.child,
     this.maxWidth = 600,
     this.withFrame = true,
     this.withScrolling = true,
+    this.innerPadding,
     super.key,
   });
   @override
@@ -36,16 +38,20 @@ class MaxWidthBody extends StatelessWidget {
                         Theme.of(context).appBarTheme.scrolledUnderElevation ??
                             4,
                     clipBehavior: Clip.hardEdge,
-                    borderRadius: BorderRadius.circular(
+                    borderRadius: BorderRadius.circular(AppConfig.borderRadius),
-                      AppConfig.borderRadius,
-                    ),
                     shadowColor: Theme.of(context).appBarTheme.shadowColor,
                     child: child,
                   )
                 : child,
           );
-          if (!withScrolling) return childWithPadding;
+          if (!withScrolling) {
+            return Padding(
+              padding: innerPadding ?? EdgeInsets.zero,
+              child: childWithPadding,
+            );
+          }
           return SingleChildScrollView(
+            padding: innerPadding,
             physics: const ScrollPhysics(),
             child: childWithPadding,
           );