diff --git a/XSDVisualiser.Desktop/App.axaml b/XSDVisualiser.Desktop/App.axaml
index 610db54..cef4d89 100644
--- a/XSDVisualiser.Desktop/App.axaml
+++ b/XSDVisualiser.Desktop/App.axaml
@@ -1,8 +1,22 @@
 <Application xmlns="https://github.com/avaloniaui"
              xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
              xmlns:fluent="using:Avalonia.Themes.Fluent"
-             x:Class="XSDVisualiser.Desktop.App">
+             x:Class="XSDVisualiser.Desktop.App"
+             RequestedThemeVariant="Light">
+  <Application.Resources>
+    <!-- App-level resource brushes for consistent, accessible colors -->
+    <SolidColorBrush x:Key="AccentBrush" Color="#2563EB"/>
+    <SolidColorBrush x:Key="AccentBrushLight" Color="#DBEAFE"/>
+    <SolidColorBrush x:Key="PanelBackgroundBrush" Color="#FFFFFFFF"/>
+    <SolidColorBrush x:Key="PanelBorderBrush" Color="#E5E7EB"/>
+    <SolidColorBrush x:Key="SubtleTextBrush" Color="#475569"/>
+    <SolidColorBrush x:Key="MutedTextBrush" Color="#64748B"/>
+    <SolidColorBrush x:Key="SeparatorBrush" Color="#E2E8F0"/>
+    <SolidColorBrush x:Key="BadgeBackgroundBrush" Color="#F1F5F9"/>
+  </Application.Resources>
+
   <Application.Styles>
-    <fluent:FluentTheme />
+    <!-- Use Fluent theme for consistent UI controls -->
+    <fluent:FluentTheme/>
   </Application.Styles>
 </Application>
diff --git a/XSDVisualiser.Desktop/MainWindow.axaml b/XSDVisualiser.Desktop/MainWindow.axaml
index 23aab81..1fafb50 100644
--- a/XSDVisualiser.Desktop/MainWindow.axaml
+++ b/XSDVisualiser.Desktop/MainWindow.axaml
@@ -3,8 +3,8 @@
         xmlns:m="clr-namespace:XSDVisualiser.Models;assembly=XSDVisualiser.Core"
         xmlns:conv="clr-namespace:XSDVisualiser.Desktop.Converters"
         x:Class="XSDVisualiser.Desktop.MainWindow"
-        x:DataType="m:SchemaModel"
-        Title="XSD Visualiser" Width="1100" Height="800">
+        x:CompileBindings="False"
+        Title="XSD Visualiser" Width="1200" Height="800">
     <Window.Resources>
         <conv:CardinalityToLabelConverter x:Key="CardinalityToLabel"/>
         <conv:OptionalToBorderBrushConverter x:Key="OptionalToBrush"/>
@@ -12,48 +12,152 @@
     </Window.Resources>
 
     <Grid RowDefinitions="Auto,*" Margin="12">
-        <StackPanel Orientation="Horizontal" Spacing="8">
-            <TextBlock Text="XSD Visualiser (Avalonia)" FontSize="18"/>
-            <Button Content="Open XSD and parse" x:Name="OpenBtn" Width="200" Margin="12,0,0,0"/>
-        </StackPanel>
+        <!-- Header -->
+        <DockPanel LastChildFill="False">
+            <TextBlock Text="XSD Visualiser" FontSize="20" FontWeight="SemiBold" Margin="0,0,12,0" DockPanel.Dock="Left"/>
+            <Button Content="Open XSD and parse" x:Name="OpenBtn" Width="220"/>
+        </DockPanel>
 
-        <ScrollViewer Grid.Row="1">
-            <TreeView x:Name="SchemaTree" ItemsSource="{Binding RootElements}">
-                <TreeView.DataTemplates>
-                    <TreeDataTemplate DataType="{x:Type m:SchemaNode}" ItemsSource="{Binding Children}">
-                        <StackPanel>
-                            <!-- Connector line from parent to this node (hidden for roots where ContentModel is null) -->
-                            <Grid Margin="0,6,0,2" IsVisible="{Binding ContentModel, Converter={x:Static ObjectConverters.IsNotNull}}">
-                                <Grid.ColumnDefinitions>
-                                    <ColumnDefinition Width="16"/>
-                                    <ColumnDefinition Width="*"/>
-                                </Grid.ColumnDefinitions>
-                                <!-- leading small elbow -->
-                                <Rectangle Grid.Column="0" Width="16" Height="2" Fill="#888" VerticalAlignment="Center"/>
-                                <Grid Grid.Column="1">
-                                    <Rectangle Height="2" Fill="#888" VerticalAlignment="Center"/>
-                                    <TextBlock Text="{Binding Cardinality, Converter={StaticResource CardinalityToLabel}}"
-                                               Background="#F0F0F0" Padding="4,0"
-                                               HorizontalAlignment="Center"/>
-                                </Grid>
-                            </Grid>
+        <!-- Body: left tree | splitter | right details -->
+        <Grid Grid.Row="1" ColumnDefinitions="*,Auto,1.6*" RowDefinitions="*">
+            <!-- Left: Tree -->
+            <Border Background="{DynamicResource PanelBackgroundBrush}"
+                    BorderBrush="{DynamicResource PanelBorderBrush}"
+                    BorderThickness="1" CornerRadius="6" Margin="0,8,8,0">
+                <ScrollViewer>
+                    <TreeView x:Name="SchemaTree" ItemsSource="{Binding RootElements}">
+                        <TreeView.DataTemplates>
+                            <TreeDataTemplate DataType="{x:Type m:SchemaNode}" ItemsSource="{Binding Children}">
+                                <StackPanel>
+                                    <!-- Connector line from parent to this node (hidden for roots where ContentModel is null) -->
+                                    <Grid Margin="0,6,0,2" IsVisible="{Binding ContentModel, Converter={x:Static ObjectConverters.IsNotNull}}">
+                                        <Grid.ColumnDefinitions>
+                                            <ColumnDefinition Width="16"/>
+                                            <ColumnDefinition Width="*"/>
+                                        </Grid.ColumnDefinitions>
+                                        <!-- leading small elbow -->
+                                        <Rectangle Grid.Column="0" Width="16" Height="2" Fill="{DynamicResource SeparatorBrush}" VerticalAlignment="Center"/>
+                                        <Grid Grid.Column="1">
+                                            <Rectangle Height="2" Fill="{DynamicResource SeparatorBrush}" VerticalAlignment="Center"/>
+                                            <TextBlock Text="{Binding Cardinality, Converter={StaticResource CardinalityToLabel}}"
+                                                       Background="{DynamicResource BadgeBackgroundBrush}" Padding="6,0"
+                                                       Foreground="{DynamicResource SubtleTextBrush}"
+                                                       HorizontalAlignment="Center"/>
+                                        </Grid>
+                                    </Grid>
 
-                            <!-- Node content -->
-                            <Border CornerRadius="4"
-                                    BorderBrush="{Binding Cardinality, Converter={StaticResource OptionalToBrush}}"
-                                    BorderThickness="{Binding Cardinality, Converter={StaticResource OptionalToThickness}}"
-                                    Padding="8" Margin="0,0,0,4">
-                                <StackPanel Orientation="Horizontal" Spacing="6">
-                                    <TextBlock Text="{Binding Name}" FontWeight="Bold"/>
-                                    <TextBlock Text="{Binding TypeName}" Foreground="#555"/>
-                                    <TextBlock Text="{Binding BuiltInType}" Foreground="#777"/>
-                                    <TextBlock Text="{Binding ContentModel}" Foreground="#999"/>
+                                    <!-- Node content -->
+                                    <Border CornerRadius="4"
+                                            BorderBrush="{Binding Cardinality, Converter={StaticResource OptionalToBrush}}"
+                                            BorderThickness="{Binding Cardinality, Converter={StaticResource OptionalToThickness}}"
+                                            Padding="8" Margin="0,0,0,6" Background="#FAFAFA">
+                                        <StackPanel Orientation="Horizontal" Spacing="10">
+                                            <TextBlock Text="{Binding Name}" FontWeight="SemiBold"/>
+                                            <TextBlock Text="{Binding TypeName}" Foreground="{DynamicResource SubtleTextBrush}"/>
+                                            <TextBlock Text="{Binding BuiltInType}" Foreground="{DynamicResource MutedTextBrush}"/>
+                                            <TextBlock Text="{Binding ContentModel}" Foreground="{DynamicResource MutedTextBrush}"/>
+                                        </StackPanel>
+                                    </Border>
                                 </StackPanel>
-                            </Border>
-                        </StackPanel>
-                    </TreeDataTemplate>
-                </TreeView.DataTemplates>
-            </TreeView>
-        </ScrollViewer>
+                            </TreeDataTemplate>
+                        </TreeView.DataTemplates>
+                    </TreeView>
+                </ScrollViewer>
+            </Border>
+
+            <!-- Splitter -->
+            <GridSplitter Grid.Column="1" Width="6" Margin="4,8" Background="{DynamicResource PanelBorderBrush}" ShowsPreview="True"/>
+
+            <!-- Right: Details -->
+            <Border Grid.Column="2" Background="{DynamicResource PanelBackgroundBrush}"
+                    BorderBrush="{DynamicResource PanelBorderBrush}"
+                    BorderThickness="1" CornerRadius="6" Margin="8,8,0,0">
+                <ScrollViewer>
+                    <ContentControl Content="{Binding #SchemaTree.SelectedItem}">
+                        <ContentControl.DataTemplates>
+                            <DataTemplate DataType="{x:Type m:SchemaNode}">
+                                <StackPanel Margin="12" Spacing="12">
+                                    <TextBlock Text="Details" FontSize="16" FontWeight="SemiBold"/>
+
+                                    <!-- General info -->
+                                    <Border BorderBrush="{DynamicResource PanelBorderBrush}" BorderThickness="1" CornerRadius="4" Padding="10">
+                                        <Grid ColumnDefinitions="Auto,*,Auto,*" RowDefinitions="Auto,Auto,Auto,Auto,Auto">
+                                            <TextBlock Text="Name:" FontWeight="Bold"/>
+                                            <TextBlock Grid.Column="1" Margin="8,0,0,0" Text="{Binding Name}"/>
+
+                                            <TextBlock Grid.Row="1" Text="Type:" FontWeight="Bold"/>
+                                            <TextBlock Grid.Column="1" Grid.Row="1" Margin="8,0,0,0" Text="{Binding TypeName}"/>
+
+                                            <TextBlock Grid.Row="2" Text="Built-in:" FontWeight="Bold"/>
+                                            <TextBlock Grid.Column="1" Grid.Row="2" Margin="8,0,0,0" Text="{Binding BuiltInType}"/>
+
+                                            <TextBlock Grid.Row="3" Text="Namespace:" FontWeight="Bold"/>
+                                            <TextBlock Grid.Column="1" Grid.Row="3" Margin="8,0,0,0" Text="{Binding Namespace}"/>
+
+                                            <TextBlock Grid.Row="4" Text="Cardinality:" FontWeight="Bold"/>
+                                            <TextBlock Grid.Column="1" Grid.Row="4" Margin="8,0,0,0" Text="{Binding Cardinality, Converter={StaticResource CardinalityToLabel}}"/>
+
+                                            <TextBlock Grid.Column="2" Text="Model:" FontWeight="Bold"/>
+                                            <TextBlock Grid.Column="3" Margin="8,0,0,0" Text="{Binding ContentModel}"/>
+                                        </Grid>
+                                    </Border>
+
+                                    <!-- Attributes list -->
+                                    <StackPanel>
+                                        <TextBlock Text="Attributes" FontWeight="SemiBold"/>
+                                        <ItemsControl ItemsSource="{Binding Attributes}">
+                                            <ItemsControl.ItemTemplate>
+                                                <DataTemplate x:DataType="m:AttributeInfo">
+                                                    <Border BorderBrush="{DynamicResource PanelBorderBrush}" BorderThickness="1" CornerRadius="4" Padding="8" Margin="0,6,0,0">
+                                                        <Grid ColumnDefinitions="Auto,*,Auto,*" RowDefinitions="Auto,Auto,Auto">
+                                                            <TextBlock Text="Name:" FontWeight="Bold"/>
+                                                            <TextBlock Grid.Column="1" Margin="8,0,0,0" Text="{Binding Name}"/>
+
+                                                            <TextBlock Grid.Row="1" Text="Type:" FontWeight="Bold"/>
+                                                            <TextBlock Grid.Column="1" Grid.Row="1" Margin="8,0,0,0" Text="{Binding TypeName}"/>
+
+                                                            <TextBlock Grid.Row="2" Text="Use:" FontWeight="Bold"/>
+                                                            <TextBlock Grid.Column="1" Grid.Row="2" Margin="8,0,0,0" Text="{Binding Use}"/>
+
+                                                            <TextBlock Grid.Column="2" Text="Built-in:" FontWeight="Bold"/>
+                                                            <TextBlock Grid.Column="3" Margin="8,0,0,0" Text="{Binding BuiltInType}"/>
+                                                        </Grid>
+                                                    </Border>
+                                                </DataTemplate>
+                                            </ItemsControl.ItemTemplate>
+                                        </ItemsControl>
+                                    </StackPanel>
+
+                                    <!-- Constraints -->
+                                    <StackPanel>
+                                        <TextBlock Text="Constraints" FontWeight="SemiBold"/>
+                                        <ContentControl Content="{Binding Constraints}">
+                                            <ContentControl.DataTemplates>
+                                                <DataTemplate x:DataType="m:ConstraintSet">
+                                                    <StackPanel Spacing="8">
+                                                        <TextBlock Text="Base Type:" FontWeight="Bold"/>
+                                                        <TextBlock Text="{Binding BaseTypeName}"/>
+
+                                                        <StackPanel>
+                                                            <TextBlock Text="Enumerations" FontWeight="SemiBold"/>
+                                                            <ItemsControl ItemsSource="{Binding Enumerations}"/>
+                                                        </StackPanel>
+
+                                                        <StackPanel>
+                                                            <TextBlock Text="Patterns" FontWeight="SemiBold"/>
+                                                            <ItemsControl ItemsSource="{Binding Patterns}"/>
+                                                        </StackPanel>
+                                                    </StackPanel>
+                                                </DataTemplate>
+                                            </ContentControl.DataTemplates>
+                                        </ContentControl>
+                                    </StackPanel>
+                                </StackPanel>
+                            </DataTemplate>
+                        </ContentControl.DataTemplates>
+                    </ContentControl>
+                </ScrollViewer>
+            </Border>
+        </Grid>
     </Grid>
 </Window>