diff --git a/CHANGELOG.md b/CHANGELOG.md
index a7f5ffc..5262111 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -15,6 +15,7 @@ au](https://solidcommunity.au/docs/solidui)
 
 ## 0.4.0 Refine and Tune
 
++ Adds additional layout width checks [0.3.6 20260326 tonypioneer]
 + Add checkbox and new webid widgets to SolidLogin() [0.3.5 20260325 tonypioneer]
 + Add WebID to SetupWizard [0.3.4 20260325 tonypioneer]
 + Login again if webid changed [0.3.3 20260319 tonypioneer]
diff --git a/lib/solidui.dart b/lib/solidui.dart
index 78963f5..21a2d6a 100644
--- a/lib/solidui.dart
+++ b/lib/solidui.dart
@@ -41,6 +41,7 @@ export 'src/widgets/solid_nav_models.dart';
 
 export 'src/widgets/solid_scaffold.dart';
 export 'src/widgets/solid_scaffold_controller.dart';
+export 'src/widgets/solid_scaffold_helpers.dart' show SolidScaffoldHelpers;
 export 'src/widgets/solid_scaffold_models.dart';
 
 export 'src/widgets/solid_status_bar.dart';
diff --git a/lib/src/constants/navigation.dart b/lib/src/constants/navigation.dart
index 7f551e4..f3fd214 100644
--- a/lib/src/constants/navigation.dart
+++ b/lib/src/constants/navigation.dart
@@ -33,16 +33,21 @@ library;
 /// Navigation constants used throughout the application.
 
 class NavigationConstants {
+  /// The width threshold for determining very narrow screen layout.
+
+  static const double veryNarrowScreenThreshold = 600.0;
+
   /// The width threshold for determining narrow/wide screen layout.
-  ///
-  /// Screens wider than this value will use the navigation rail,
-  /// while narrower screens will use the navigation drawer.
 
   static const double narrowScreenThreshold = 800.0;
 
-  /// The width threshold for determining very narrow screen layout.
+  /// The width threshold for wide screen layout.
 
-  static const double veryNarrowScreenThreshold = 600.0;
+  static const double wideScreenThreshold = 900.0;
+
+  /// The width threshold for very wide screen layout.
+
+  static const double veryWideScreenThreshold = 1000.0;
 
   /// Minimum width for the navigation rail.
 
diff --git a/lib/src/constants/ui_window.dart b/lib/src/constants/ui_window.dart
index 408d2ac..f841f5f 100644
--- a/lib/src/constants/ui_window.dart
+++ b/lib/src/constants/ui_window.dart
@@ -30,33 +30,78 @@ library;
 
 import 'package:flutter/material.dart';
 
-/// Thresholds for window size.
+import 'package:solidui/src/constants/navigation.dart';
+
+/// Responsive layout helpers using [LayoutBuilder] constraints.
 
 class WindowSize {
   /// Small width threshold.
 
-  static const double smallWidthLimit = 600;
+  static const double smallWidthLimit =
+      NavigationConstants.veryNarrowScreenThreshold;
 
   /// Small height threshold.
 
   static const double smallHeightLimit = 600;
 
-  /// Boolean describing whether the parent widget is narrow.
-  /// Derived from the box constraints found by LayoutBuilder().
-  ///
-  /// Arguments:
-  /// - [constraints] - The box constraints of the parent widget
-  ///   where LayoutBuilder() was called.
+  /// Legacy method — equivalent to [isVeryNarrow].
 
   bool isNarrowWindow(BoxConstraints constraints) {
-    final bool isNarrow;
-    if (constraints.maxWidth < WindowSize.smallWidthLimit) {
-      isNarrow = true;
-    } else {
-      isNarrow = false;
-    }
+    return isVeryNarrow(constraints);
+  }
+
+  /// Whether [constraints] width is below the very narrow threshold.
+
+  static bool isVeryNarrow(
+    BoxConstraints constraints, {
+    double threshold = NavigationConstants.veryNarrowScreenThreshold,
+  }) {
+    return constraints.maxWidth < threshold;
+  }
 
-    return isNarrow;
+  /// Whether [constraints] width falls in the narrow range, i.e. between
+  /// [veryNarrowThreshold] (inclusive) and [narrowThreshold] (exclusive).
+
+  static bool isNarrow(
+    BoxConstraints constraints, {
+    double veryNarrowThreshold = NavigationConstants.veryNarrowScreenThreshold,
+    double narrowThreshold = NavigationConstants.narrowScreenThreshold,
+  }) {
+    return constraints.maxWidth >= veryNarrowThreshold &&
+        constraints.maxWidth < narrowThreshold;
+  }
+
+  /// Whether [constraints] width falls in the medium range, i.e. between
+  /// [narrowThreshold] (inclusive) and [wideThreshold] (exclusive).
+
+  static bool isMedium(
+    BoxConstraints constraints, {
+    double narrowThreshold = NavigationConstants.narrowScreenThreshold,
+    double wideThreshold = NavigationConstants.wideScreenThreshold,
+  }) {
+    return constraints.maxWidth >= narrowThreshold &&
+        constraints.maxWidth < wideThreshold;
+  }
+
+  /// Whether [constraints] width falls in the wide range, i.e. between
+  /// [wideThreshold] (inclusive) and [veryWideThreshold] (exclusive).
+
+  static bool isWide(
+    BoxConstraints constraints, {
+    double wideThreshold = NavigationConstants.wideScreenThreshold,
+    double veryWideThreshold = NavigationConstants.veryWideScreenThreshold,
+  }) {
+    return constraints.maxWidth >= wideThreshold &&
+        constraints.maxWidth < veryWideThreshold;
+  }
+
+  /// Whether [constraints] width exceeds the very wide threshold.
+
+  static bool isVeryWide(
+    BoxConstraints constraints, {
+    double threshold = NavigationConstants.veryWideScreenThreshold,
+  }) {
+    return constraints.maxWidth >= threshold;
   }
 }
 
@@ -87,9 +132,7 @@ class ListItemSize {
 
     final double cardAspectRatio;
 
-    // Derive card aspect ratio (width / height).
-
-    if (constraints.maxWidth < WindowSize.smallWidthLimit) {
+    if (WindowSize.isVeryNarrow(constraints)) {
       cardAspectRatio = constraints.maxWidth / compressedItemHeight;
     } else {
       cardAspectRatio = constraints.maxWidth / uncompressedItemHeight;
diff --git a/lib/src/screens/initial_setup_widgets/res_create_form_submission.dart b/lib/src/screens/initial_setup_widgets/res_create_form_submission.dart
index c1d4282..7ccd850 100644
--- a/lib/src/screens/initial_setup_widgets/res_create_form_submission.dart
+++ b/lib/src/screens/initial_setup_widgets/res_create_form_submission.dart
@@ -59,7 +59,7 @@ ElevatedButton resCreateFormSubmission(
   // Use MediaQuery to determine the screen width and adjust the font size
   // accordingly.
 
-  final screenWidth = MediaQuery.of(context).size.width;
+  final screenWidth = MediaQuery.sizeOf(context).width;
   final isSmallDevice =
       screenWidth < 360; // A threshold for small devices, can be adjusted.
 
diff --git a/lib/src/widgets/build_message_container.dart b/lib/src/widgets/build_message_container.dart
index 75ae5ac..7f479ab 100644
--- a/lib/src/widgets/build_message_container.dart
+++ b/lib/src/widgets/build_message_container.dart
@@ -95,7 +95,7 @@ Container buildMsgBox(
   // ignore: unused_local_variable
   var isRTL = false;
 
-  final size = MediaQuery.of(context).size;
+  final size = MediaQuery.sizeOf(context);
   final loc = Localizations.maybeLocaleOf(context);
   final localeLanguageCode = loc?.languageCode;
 
diff --git a/lib/src/widgets/shared_resources_table.dart b/lib/src/widgets/shared_resources_table.dart
index cc872d3..1a1e9b7 100644
--- a/lib/src/widgets/shared_resources_table.dart
+++ b/lib/src/widgets/shared_resources_table.dart
@@ -49,7 +49,7 @@ Widget buildSharedResourcesTable(
   Map<dynamic, dynamic> sharedResMap,
   Widget parentWidget,
 ) {
-  final cWidth = MediaQuery.of(context).size.width * 0.18;
+  final cWidth = MediaQuery.sizeOf(context).width * 0.18;
   DataColumn buildDataColumn(String title, String tooltip) {
     return DataColumn(
       label: Expanded(child: Center(child: Text(title))),
diff --git a/lib/src/widgets/solid_file_helpers.dart b/lib/src/widgets/solid_file_helpers.dart
index 992c22e..355b522 100644
--- a/lib/src/widgets/solid_file_helpers.dart
+++ b/lib/src/widgets/solid_file_helpers.dart
@@ -45,7 +45,7 @@ class SolidFileHelpers {
     if (forceWideScreen != null) {
       return forceWideScreen;
     }
-    return MediaQuery.of(context).size.width > 800;
+    return MediaQuery.sizeOf(context).width > 800;
   }
 
   /// Gets the effective browser height.
@@ -54,7 +54,7 @@ class SolidFileHelpers {
     if (browserHeight != null) {
       return browserHeight;
     }
-    return MediaQuery.of(context).size.height * 0.7;
+    return MediaQuery.sizeOf(context).height * 0.7;
   }
 
   /// Gets the effective upload configuration, either from the provided config
diff --git a/lib/src/widgets/solid_login_build_helper.dart b/lib/src/widgets/solid_login_build_helper.dart
index b1be9f3..2923695 100644
--- a/lib/src/widgets/solid_login_build_helper.dart
+++ b/lib/src/widgets/solid_login_build_helper.dart
@@ -130,12 +130,12 @@ class SolidLoginBuildHelper {
           behavior: HitTestBehavior.deferToChild,
           child: SafeArea(
             child: DecoratedBox(
-              decoration: isNarrowScreen(context)
+              decoration: isNarrowLoginScreen(context)
                   ? loginBoxDecor
                   : const BoxDecoration(),
               child: Row(
                 children: [
-                  isNarrowScreen(context)
+                  isNarrowLoginScreen(context)
                       ? Container()
                       : Expanded(
                           flex: 7,
diff --git a/lib/src/widgets/solid_login_helper.dart b/lib/src/widgets/solid_login_helper.dart
index fcbe575..a75b4b4 100644
--- a/lib/src/widgets/solid_login_helper.dart
+++ b/lib/src/widgets/solid_login_helper.dart
@@ -40,12 +40,12 @@ import 'package:markdown_tooltip/markdown_tooltip.dart';
 const int narrowScreenLimit = 1175;
 const int veryNarrowScreenLimit = 750;
 
-double screenWidth(BuildContext context) => MediaQuery.of(context).size.width;
+double screenWidth(BuildContext context) => MediaQuery.sizeOf(context).width;
 
-bool isNarrowScreen(BuildContext context) =>
+bool isNarrowLoginScreen(BuildContext context) =>
     screenWidth(context) < narrowScreenLimit;
 
-bool isVeryNarrowScreen(BuildContext context) =>
+bool isVeryNarrowLoginScreen(BuildContext context) =>
     screenWidth(context) < veryNarrowScreenLimit;
 
 /// Button styles used in the Solid Login widget.
diff --git a/lib/src/widgets/solid_login_panel.dart b/lib/src/widgets/solid_login_panel.dart
index 8797986..0198802 100644
--- a/lib/src/widgets/solid_login_panel.dart
+++ b/lib/src/widgets/solid_login_panel.dart
@@ -112,7 +112,7 @@ class SolidLoginPanel {
                   if (isRequired)
                     Expanded(
                       child: SizedBox(
-                        width: MediaQuery.of(context).size.width * 0.5,
+                        width: MediaQuery.sizeOf(context).width * 0.5,
                         child: infoButton,
                       ),
                     ),
@@ -178,7 +178,9 @@ class SolidLoginPanel {
     required SolidLoginThemeMode currentTheme,
   }) {
     final loginPanelInset =
-        (isVeryNarrowScreen(context) || !isNarrowScreen(context)) ? 0.05 : 0.25;
+        (isVeryNarrowLoginScreen(context) || !isNarrowLoginScreen(context))
+            ? 0.05
+            : 0.25;
 
     return Container(
       margin: EdgeInsets.symmetric(
diff --git a/lib/src/widgets/solid_nav_bar.dart b/lib/src/widgets/solid_nav_bar.dart
index 9d42f20..3ac8bf5 100644
--- a/lib/src/widgets/solid_nav_bar.dart
+++ b/lib/src/widgets/solid_nav_bar.dart
@@ -100,7 +100,7 @@ class SolidNavBar extends StatelessWidget {
         child: SingleChildScrollView(
           child: ConstrainedBox(
             constraints: BoxConstraints(
-              minHeight: MediaQuery.of(context).size.height,
+              minHeight: MediaQuery.sizeOf(context).height,
             ),
             child: IntrinsicHeight(
               child: NavigationRail(
diff --git a/lib/src/widgets/solid_nav_drawer.dart b/lib/src/widgets/solid_nav_drawer.dart
index 0344d13..94c4c30 100644
--- a/lib/src/widgets/solid_nav_drawer.dart
+++ b/lib/src/widgets/solid_nav_drawer.dart
@@ -167,7 +167,7 @@ class _SolidNavDrawerState extends State<SolidNavDrawer> {
             ),
           ),
       child: ListView(
-        padding: EdgeInsets.only(top: MediaQuery.of(context).padding.top),
+        padding: EdgeInsets.only(top: MediaQuery.paddingOf(context).top),
         children: <Widget>[
           if (widget.userInfo != null)
             SolidNavDrawerHeader.build(
diff --git a/lib/src/widgets/solid_nav_drawer_header.dart b/lib/src/widgets/solid_nav_drawer_header.dart
index 8379e29..8598145 100644
--- a/lib/src/widgets/solid_nav_drawer_header.dart
+++ b/lib/src/widgets/solid_nav_drawer_header.dart
@@ -58,7 +58,7 @@ class SolidNavDrawerHeader {
     return Container(
       padding: EdgeInsets.only(
         top: NavigationConstants.userHeaderTopPadding +
-            MediaQuery.of(context).padding.top,
+            MediaQuery.paddingOf(context).top,
         bottom: bottomPadding,
       ),
       decoration: BoxDecoration(color: theme.colorScheme.primaryContainer),
diff --git a/lib/src/widgets/solid_scaffold_appbar_builder.dart b/lib/src/widgets/solid_scaffold_appbar_builder.dart
index 4e820a5..fbb7c2e 100644
--- a/lib/src/widgets/solid_scaffold_appbar_builder.dart
+++ b/lib/src/widgets/solid_scaffold_appbar_builder.dart
@@ -59,6 +59,7 @@ class SolidScaffoldAppBarBuilder {
     bool showLogout = true,
     void Function(BuildContext)? onLogout,
     void Function(BuildContext)? onLogin,
+    required BoxConstraints constraints,
   }) {
     SolidAppBarActionsManager.initializeIfNeeded(
       config,
@@ -66,19 +67,19 @@ class SolidScaffoldAppBarBuilder {
       hasLogout: showLogout,
     );
 
-    final isWideScreen = !hideNavRail &&
-        SolidScaffoldHelpers.isWideScreen(context, narrowScreenThreshold);
-    final screenWidth = MediaQuery.of(context).size.width;
+    final layoutWidth = constraints.maxWidth;
+    final isNarrowScreen = hideNavRail ||
+        SolidScaffoldHelpers.isNarrowScreen(
+          constraints,
+          narrowThreshold: narrowScreenThreshold,
+        ) ||
+        SolidScaffoldHelpers.isVeryNarrowScreen(constraints);
     final theme = Theme.of(context);
 
-    // Build action buttons.
-
     List<Widget> actions = [];
 
-    // Add version widget if configured and screen is not too narrow.
-
     if (config.versionConfig != null &&
-        screenWidth >= config.veryNarrowScreenThreshold &&
+        layoutWidth >= config.veryNarrowScreenThreshold &&
         shouldShowVersion) {
       actions.add(
         SolidScaffoldHelpers.buildVersionWidget(
@@ -90,11 +91,9 @@ class SolidScaffoldAppBarBuilder {
       actions.add(const Gap(8));
     }
 
-    // Build ordered actions based on preferences.
-
     final orderedActions = SolidAppBarOrderedActionsBuilder.build(
       config: config,
-      screenWidth: screenWidth,
+      layoutWidth: layoutWidth,
       themeToggle: themeToggle,
       currentThemeMode: currentThemeMode,
       themeToggleCallback: themeToggleCallback,
@@ -106,12 +105,10 @@ class SolidScaffoldAppBarBuilder {
     );
     actions.addAll(orderedActions);
 
-    // Handle overflow menu if on narrow screen.
-
     SolidAppBarOverflowHandler.handleOverflowMenu(
       actions,
       config,
-      screenWidth,
+      layoutWidth,
       themeToggle,
       currentThemeMode,
       themeToggleCallback,
@@ -125,7 +122,7 @@ class SolidScaffoldAppBarBuilder {
     return AppBar(
       title: Text(config.title),
       backgroundColor: config.backgroundColor,
-      automaticallyImplyLeading: !isWideScreen,
+      automaticallyImplyLeading: isNarrowScreen,
       actions: actions.isEmpty ? null : actions,
     );
   }
diff --git a/lib/src/widgets/solid_scaffold_appbar_ordered_actions.dart b/lib/src/widgets/solid_scaffold_appbar_ordered_actions.dart
index 1520fdc..69c1f04 100644
--- a/lib/src/widgets/solid_scaffold_appbar_ordered_actions.dart
+++ b/lib/src/widgets/solid_scaffold_appbar_ordered_actions.dart
@@ -52,7 +52,7 @@ class SolidAppBarOrderedActionsBuilder {
 
   static List<Widget> build({
     required SolidAppBarConfig config,
-    required double screenWidth,
+    required double layoutWidth,
     required SolidThemeToggleConfig? themeToggle,
     required ThemeMode currentThemeMode,
     required VoidCallback? themeToggleCallback,
@@ -63,33 +63,33 @@ class SolidAppBarOrderedActionsBuilder {
     void Function(BuildContext)? onLogin,
   }) {
     final List<_OrderedAction> orderedActions = [];
-    final isNarrowScreen = screenWidth < config.narrowScreenThreshold;
+    final isVeryNarrowScreen = layoutWidth < config.veryNarrowScreenThreshold;
 
     _addThemeToggle(
       orderedActions,
       themeToggle,
       config,
-      screenWidth,
-      isNarrowScreen,
+      layoutWidth,
+      isVeryNarrowScreen,
       currentThemeMode,
       themeToggleCallback,
     );
-    _addCustomActions(orderedActions, config, screenWidth, isNarrowScreen);
-    _addOverflowItems(orderedActions, config, isNarrowScreen);
+    _addCustomActions(orderedActions, config, layoutWidth, isVeryNarrowScreen);
+    _addOverflowItems(orderedActions, config, isVeryNarrowScreen);
     _addAuthButton(
       orderedActions,
       showLogout,
       onLogout,
       onLogin,
-      isNarrowScreen,
+      isVeryNarrowScreen,
       context,
     );
     _addAboutButton(
       orderedActions,
       aboutConfig,
       config,
-      screenWidth,
-      isNarrowScreen,
+      layoutWidth,
+      isVeryNarrowScreen,
     );
 
     orderedActions.sort((a, b) => a.order.compareTo(b.order));
@@ -100,8 +100,8 @@ class SolidAppBarOrderedActionsBuilder {
     List<_OrderedAction> orderedActions,
     SolidThemeToggleConfig? themeToggle,
     SolidAppBarConfig config,
-    double screenWidth,
-    bool isNarrowScreen,
+    double layoutWidth,
+    bool isVeryNarrowScreen,
     ThemeMode currentThemeMode,
     VoidCallback? themeToggleCallback,
   ) {
@@ -115,11 +115,11 @@ class SolidAppBarOrderedActionsBuilder {
     final order = actionConfig?.order ?? 0;
 
     final shouldShow = isVisible &&
-        (!isNarrowScreen || !isInOverflow) &&
+        (!isVeryNarrowScreen || !isInOverflow) &&
         SolidAppBarVisibilityHelper.shouldShowThemeToggle(
           themeToggle,
           config,
-          screenWidth,
+          layoutWidth,
         );
 
     if (shouldShow) {
@@ -139,8 +139,8 @@ class SolidAppBarOrderedActionsBuilder {
   static void _addCustomActions(
     List<_OrderedAction> orderedActions,
     SolidAppBarConfig config,
-    double screenWidth,
-    bool isNarrowScreen,
+    double layoutWidth,
+    bool isVeryNarrowScreen,
   ) {
     for (int i = 0; i < config.actions.length; i++) {
       final action = config.actions[i];
@@ -151,11 +151,11 @@ class SolidAppBarOrderedActionsBuilder {
       final order = actionConfig?.order ?? (100 + i);
 
       final shouldShow = isVisible &&
-          (!isNarrowScreen || !isInOverflow) &&
+          (!isVeryNarrowScreen || !isInOverflow) &&
           SolidAppBarVisibilityHelper.shouldShowAction(
             action,
             config,
-            screenWidth,
+            layoutWidth,
           );
 
       if (shouldShow) {
@@ -180,7 +180,7 @@ class SolidAppBarOrderedActionsBuilder {
   static void _addOverflowItems(
     List<_OrderedAction> orderedActions,
     SolidAppBarConfig config,
-    bool isNarrowScreen,
+    bool isVeryNarrowScreen,
   ) {
     for (int i = 0; i < config.overflowItems.length; i++) {
       final item = config.overflowItems[i];
@@ -189,7 +189,7 @@ class SolidAppBarOrderedActionsBuilder {
       final isInOverflow = actionConfig?.showInOverflow ?? true;
       final order = actionConfig?.order ?? (200 + i);
 
-      if (isVisible && (!isNarrowScreen || !isInOverflow)) {
+      if (isVisible && (!isVeryNarrowScreen || !isInOverflow)) {
         Widget iconButton = IconButton(
           icon: Icon(item.icon),
           onPressed: item.onSelected,
@@ -210,7 +210,7 @@ class SolidAppBarOrderedActionsBuilder {
     bool showLogout,
     void Function(BuildContext)? onLogout,
     void Function(BuildContext)? onLogin,
-    bool isNarrowScreen,
+    bool isVeryNarrowScreen,
     BuildContext context,
   ) {
     final actionConfig = SolidAppBarActionsManager.getActionConfig(
@@ -220,7 +220,7 @@ class SolidAppBarOrderedActionsBuilder {
     final isInOverflow = actionConfig?.showInOverflow ?? false;
     final order = actionConfig?.order ?? 400;
 
-    if (isVisible && (!isNarrowScreen || !isInOverflow)) {
+    if (isVisible && (!isVeryNarrowScreen || !isInOverflow)) {
       orderedActions.add(
         _OrderedAction(
           order: order,
@@ -238,12 +238,12 @@ class SolidAppBarOrderedActionsBuilder {
     List<_OrderedAction> orderedActions,
     SolidAboutConfig aboutConfig,
     SolidAppBarConfig config,
-    double screenWidth,
-    bool isNarrowScreen,
+    double layoutWidth,
+    bool isVeryNarrowScreen,
   ) {
     if (!aboutConfig.enabled ||
         !aboutConfig.shouldShow(
-          screenWidth,
+          layoutWidth,
           config.narrowScreenThreshold,
           config.veryNarrowScreenThreshold,
         )) {
@@ -257,7 +257,7 @@ class SolidAppBarOrderedActionsBuilder {
     final isInOverflow = actionConfig?.showInOverflow ?? false;
     final order = actionConfig?.order ?? 900;
 
-    if (isVisible && (!isNarrowScreen || !isInOverflow)) {
+    if (isVisible && (!isVeryNarrowScreen || !isInOverflow)) {
       orderedActions.add(
         _OrderedAction(
           order: order,
diff --git a/lib/src/widgets/solid_scaffold_appbar_overflow.dart b/lib/src/widgets/solid_scaffold_appbar_overflow.dart
index f31b654..f9e8ece 100644
--- a/lib/src/widgets/solid_scaffold_appbar_overflow.dart
+++ b/lib/src/widgets/solid_scaffold_appbar_overflow.dart
@@ -49,7 +49,7 @@ class SolidAppBarOverflowHandler {
   static void handleOverflowMenu(
     List<Widget> actions,
     SolidAppBarConfig config,
-    double screenWidth,
+    double layoutWidth,
     SolidThemeToggleConfig? themeToggle,
     ThemeMode currentThemeMode,
     VoidCallback? themeToggleCallback,
@@ -59,14 +59,12 @@ class SolidAppBarOverflowHandler {
     void Function(BuildContext)? onLogout,
     void Function(BuildContext)? onLogin,
   }) {
-    // Use narrowScreenThreshold to determine when to show overflow menu.
+    final isVeryNarrowScreen = layoutWidth < config.veryNarrowScreenThreshold;
 
-    final isNarrowScreen = screenWidth < config.narrowScreenThreshold;
+    // Only show overflow menu on very narrow screens.
+    // On wider screens, all buttons are displayed directly in AppBar.
 
-    // Only show overflow menu on narrow screens.
-    // On wide screens, all buttons are displayed directly in AppBar.
-
-    if (!isNarrowScreen) return;
+    if (!isVeryNarrowScreen) return;
 
     actions.add(
       _buildOverflowMenu(
diff --git a/lib/src/widgets/solid_scaffold_appbar_visibility.dart b/lib/src/widgets/solid_scaffold_appbar_visibility.dart
index b203dad..213b05c 100644
--- a/lib/src/widgets/solid_scaffold_appbar_visibility.dart
+++ b/lib/src/widgets/solid_scaffold_appbar_visibility.dart
@@ -34,38 +34,40 @@ import 'package:solidui/src/widgets/solid_theme_models.dart';
 /// Provides visibility checks for AppBar actions.
 
 class SolidAppBarVisibilityHelper {
-  /// Determines if an action should be shown based on screen width.
+  /// Determines if an action should be shown based on the available
+  /// layout width from [LayoutBuilder] constraints.
 
   static bool shouldShowAction(
     SolidAppBarAction action,
     SolidAppBarConfig config,
-    double screenWidth,
+    double layoutWidth,
   ) {
     if (!action.showOnVeryNarrowScreen &&
-        screenWidth < config.veryNarrowScreenThreshold) {
+        layoutWidth < config.veryNarrowScreenThreshold) {
       return false;
     } else if (!action.showOnNarrowScreen &&
-        screenWidth < config.narrowScreenThreshold) {
+        layoutWidth < config.narrowScreenThreshold) {
       return false;
     }
     return true;
   }
 
-  /// Determines if theme toggle should be shown.
+  /// Determines if theme toggle should be shown based on the available
+  /// layout width from [LayoutBuilder] constraints.
 
   static bool shouldShowThemeToggle(
     SolidThemeToggleConfig? themeToggle,
     SolidAppBarConfig config,
-    double screenWidth,
+    double layoutWidth,
   ) {
     if (themeToggle == null || !themeToggle.enabled) return false;
     if (!themeToggle.showInAppBarActions) return false;
 
     if (!themeToggle.showOnVeryNarrowScreen &&
-        screenWidth < config.veryNarrowScreenThreshold) {
+        layoutWidth < config.veryNarrowScreenThreshold) {
       return false;
     } else if (!themeToggle.showOnNarrowScreen &&
-        screenWidth < config.narrowScreenThreshold) {
+        layoutWidth < config.narrowScreenThreshold) {
       return false;
     }
 
diff --git a/lib/src/widgets/solid_scaffold_build_helper.dart b/lib/src/widgets/solid_scaffold_build_helper.dart
index 47ffd61..a46d94f 100644
--- a/lib/src/widgets/solid_scaffold_build_helper.dart
+++ b/lib/src/widgets/solid_scaffold_build_helper.dart
@@ -120,6 +120,7 @@ class SolidScaffoldBuildHelper {
 
   static Widget buildConfiguredScaffold({
     required BuildContext context,
+    required BoxConstraints constraints,
     required GlobalKey<ScaffoldState> scaffoldKey,
     required SolidScaffoldInternalConfig config,
     required bool isWideScreen,
@@ -166,6 +167,7 @@ class SolidScaffoldBuildHelper {
           hideNavRail: config.hideNavRail,
           showLogout: config.onLogout != null,
           onLogout: config.onLogout,
+          constraints: constraints,
         ),
       ),
       buildDrawer: () {
diff --git a/lib/src/widgets/solid_scaffold_helpers.dart b/lib/src/widgets/solid_scaffold_helpers.dart
index e40c5c2..d6783b2 100644
--- a/lib/src/widgets/solid_scaffold_helpers.dart
+++ b/lib/src/widgets/solid_scaffold_helpers.dart
@@ -33,6 +33,7 @@ import 'package:flutter/material.dart';
 import 'package:markdown_tooltip/markdown_tooltip.dart';
 import 'package:version_widget/version_widget.dart';
 
+import 'package:solidui/src/constants/ui_window.dart';
 import 'package:solidui/src/widgets/solid_about_models.dart';
 import 'package:solidui/src/widgets/solid_nav_models.dart';
 import 'package:solidui/src/widgets/solid_overflow_menu_helpers.dart';
@@ -151,10 +152,43 @@ class SolidScaffoldHelpers {
   static List<Widget> buildOverflowIconButtons(SolidAppBarConfig config) =>
       SolidOverflowMenuHelpers.buildOverflowIconButtons(config);
 
-  /// Determines if screen is wide.
+  /// Delegates to [WindowSize.isNarrow] using [BoxConstraints].
 
-  static bool isWideScreen(BuildContext context, double narrowScreenThreshold) {
-    return MediaQuery.of(context).size.width > narrowScreenThreshold;
+  static bool isNarrowScreen(
+    BoxConstraints constraints, {
+    double? narrowThreshold,
+  }) {
+    if (narrowThreshold != null) {
+      return WindowSize.isNarrow(
+        constraints,
+        narrowThreshold: narrowThreshold,
+      );
+    }
+    return WindowSize.isNarrow(constraints);
+  }
+
+  /// Delegates to [WindowSize.isVeryNarrow] using [BoxConstraints].
+
+  static bool isVeryNarrowScreen(BoxConstraints constraints) {
+    return WindowSize.isVeryNarrow(constraints);
+  }
+
+  /// Delegates to [WindowSize.isMedium] using [BoxConstraints].
+
+  static bool isMedScreen(BoxConstraints constraints) {
+    return WindowSize.isMedium(constraints);
+  }
+
+  /// Delegates to [WindowSize.isWide] using [BoxConstraints].
+
+  static bool isWideScreen(BoxConstraints constraints) {
+    return WindowSize.isWide(constraints);
+  }
+
+  /// Delegates to [WindowSize.isVeryWide] using [BoxConstraints].
+
+  static bool isVeryWideScreen(BoxConstraints constraints) {
+    return WindowSize.isVeryWide(constraints);
   }
 
   /// Gets effective child widget.
@@ -257,6 +291,7 @@ class SolidScaffoldHelpers {
     bool showLogout = true,
     void Function(BuildContext)? onLogout,
     void Function(BuildContext)? onLogin,
+    required BoxConstraints constraints,
   }) {
     if (appBar == null) return null;
     if (appBar is! SolidAppBarConfig) return null;
@@ -274,6 +309,7 @@ class SolidScaffoldHelpers {
       showLogout: showLogout,
       onLogout: onLogout,
       onLogin: onLogin,
+      constraints: constraints,
     );
   }
 
diff --git a/lib/src/widgets/solid_scaffold_state.dart b/lib/src/widgets/solid_scaffold_state.dart
index aba9363..c69323a 100644
--- a/lib/src/widgets/solid_scaffold_state.dart
+++ b/lib/src/widgets/solid_scaffold_state.dart
@@ -167,9 +167,14 @@ class SolidScaffoldState extends State<SolidScaffold> {
     }
   }
 
-  bool _isWideScreen(BuildContext c) =>
-      !widget.hideNavRail &&
-      SolidScaffoldHelpers.isWideScreen(c, widget.narrowScreenThreshold);
+  bool _isNarrowScreen(BoxConstraints constraints) {
+    return widget.hideNavRail ||
+        SolidScaffoldHelpers.isNarrowScreen(
+          constraints,
+          narrowThreshold: widget.narrowScreenThreshold,
+        ) ||
+        SolidScaffoldHelpers.isVeryNarrowScreen(constraints);
+  }
 
   bool _getUsesInternalManagement() => _cachedUsesInternalManagement ??=
       SolidScaffoldHelpers.getUsesInternalManagement(widget.themeToggle);
@@ -188,49 +193,54 @@ class SolidScaffoldState extends State<SolidScaffold> {
 
   @override
   Widget build(BuildContext context) {
-    final isWide = _isWideScreen(context);
-    final isCompat = widget.menu == null;
-    final bodyContent = isCompat
-        ? widget.body
-        : SolidScaffoldLayoutBuilder.buildBody(
-            context,
-            isWide,
-            SolidScaffoldHelpers.convertToNavTabs(widget.menu),
-            _currentSelectedIndex,
-            SolidScaffoldHelpers.getEffectiveChild(
-              widget.menu,
-              _currentSelectedIndex,
-              widget.child,
-              widget.body,
-              widget.bodyOverride ?? widget.controller?.currentSubpage,
-            ),
-            _onMenuSelected,
-            widget.onShowAlert,
-          );
-
-    return NotificationListener<SecurityKeyStatusChangedNotification>(
-      onNotification: (n) {
-        Future.delayed(const Duration(milliseconds: 300), () {
-          securityKeyNotifier.refreshStatus();
-          _loadCurrentWebId();
-        });
-        return true;
+    return LayoutBuilder(
+      builder: (context, constraints) {
+        final isNarrow = _isNarrowScreen(constraints);
+        final isCompat = widget.menu == null;
+        final bodyContent = isCompat
+            ? widget.body
+            : SolidScaffoldLayoutBuilder.buildBody(
+                context,
+                !isNarrow,
+                SolidScaffoldHelpers.convertToNavTabs(widget.menu),
+                _currentSelectedIndex,
+                SolidScaffoldHelpers.getEffectiveChild(
+                  widget.menu,
+                  _currentSelectedIndex,
+                  widget.child,
+                  widget.body,
+                  widget.bodyOverride ?? widget.controller?.currentSubpage,
+                ),
+                _onMenuSelected,
+                widget.onShowAlert,
+              );
+
+        return NotificationListener<SecurityKeyStatusChangedNotification>(
+          onNotification: (n) {
+            Future.delayed(const Duration(milliseconds: 300), () {
+              securityKeyNotifier.refreshStatus();
+              _loadCurrentWebId();
+            });
+            return true;
+          },
+          child: SolidScaffoldWidgetBuilder.buildFromWidget(
+            context: context,
+            constraints: constraints,
+            scaffoldKey: _scaffoldKey,
+            widget: widget,
+            isWideScreen: !isNarrow,
+            isCompatibilityMode: isCompat,
+            bodyContent: bodyContent,
+            isKeySaved: _isKeySaved,
+            currentSelectedIndex: _currentSelectedIndex,
+            onMenuSelected: _onMenuSelected,
+            getUsesInternalManagement: _getUsesInternalManagement,
+            shouldShowVersion: _shouldShowVersion,
+            getVersionToDisplay: _getVersionToDisplay,
+            currentWebId: _currentWebId,
+          ),
+        );
       },
-      child: SolidScaffoldWidgetBuilder.buildFromWidget(
-        context: context,
-        scaffoldKey: _scaffoldKey,
-        widget: widget,
-        isWideScreen: isWide,
-        isCompatibilityMode: isCompat,
-        bodyContent: bodyContent,
-        isKeySaved: _isKeySaved,
-        currentSelectedIndex: _currentSelectedIndex,
-        onMenuSelected: _onMenuSelected,
-        getUsesInternalManagement: _getUsesInternalManagement,
-        shouldShowVersion: _shouldShowVersion,
-        getVersionToDisplay: _getVersionToDisplay,
-        currentWebId: _currentWebId,
-      ),
     );
   }
 }
diff --git a/lib/src/widgets/solid_scaffold_widget_builder.dart b/lib/src/widgets/solid_scaffold_widget_builder.dart
index ef777a6..53c3070 100644
--- a/lib/src/widgets/solid_scaffold_widget_builder.dart
+++ b/lib/src/widgets/solid_scaffold_widget_builder.dart
@@ -114,6 +114,7 @@ class SolidScaffoldWidgetBuilder {
 
   static Widget buildFromWidget({
     required BuildContext context,
+    required BoxConstraints constraints,
     required GlobalKey<ScaffoldState> scaffoldKey,
     required SolidScaffold widget,
     required bool isWideScreen,
@@ -127,8 +128,6 @@ class SolidScaffoldWidgetBuilder {
     required String Function() getVersionToDisplay,
     String? currentWebId,
   }) {
-    // Get the effective login/logout callbacks (built-in or custom).
-
     final effectiveLogout = _getEffectiveLogout(widget);
     final effectiveLogin = _getEffectiveLogin(widget);
 
@@ -167,6 +166,7 @@ class SolidScaffoldWidgetBuilder {
           showLogout: widget.showLogout,
           onLogout: effectiveLogout,
           onLogin: effectiveLogin,
+          constraints: constraints,
         ),
       ),
       buildDrawer: () {
diff --git a/pubspec.yaml b/pubspec.yaml
index 6bfbe33..d4b2155 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,10 +1,10 @@
 name: solidui
-description: "A UI library for building Solid applications with Flutter."
-version: 0.3.5
+description: 'A UI library for building Solid applications with Flutter.'
+version: 0.3.6
 homepage: https://github.com/anusii/solidui
 
 environment:
-  sdk: ">=3.2.3 <4.0.0"
+  sdk: '>=3.2.3 <4.0.0'
 
 # To automatically upgrade package dependencies to the latest versions:
 #