some fixes and default resources

Launcher.Client.Avalonia/GUI/App.axaml

@@ -18,7 +18,13 @@
 
         <Style Selector="TextBox.MyTextBoxStyle" />
         <Style Selector="Label.MyLabelStyle" />
-        <Style Selector="Button.MyButtonStyle" />
+        <Style Selector="Button.MyButtonStyle" >
+            <Setter Property="Background" Value="Transparent"/>
+            <Setter Property="HorizontalAlignment" Value="Stretch"/>
+            <Setter Property="VerticalAlignment" Value="Stretch"/>
+            <Setter Property="HorizontalContentAlignment" Value="Center"/>
+            <Setter Property="VerticalContentAlignment" Value="Center"/>
+        </Style>
 
     </Application.Styles>
 </Application>

Launcher.Client.Avalonia/GUI/LauncherWindow.axaml

@@ -8,7 +8,7 @@
         MinWidth="800"
         MinHeight="500"
         Background="{DynamicResource MyBackgroundColor}">
-    <Grid ColumnDefinitions="5,*,5" RowDefinitions="5,40,5,*,5">
+    <Grid ColumnDefinitions="5,*,5" RowDefinitions="5,35,5,*,5">
         <Image x:Name="BackgroundImage"
                Grid.RowSpan="5"
                Grid.ColumnSpan="3"

Launcher.Client.Avalonia/GUI/MessageBox.axaml.cs

@@ -5,9 +5,6 @@ public partial class MessageBox : Window
     public MessageBox()
     {
         InitializeComponent();
-#if DEBUG
-            this.AttachDevTools();
-#endif
     }
 
     public static void Show(string title, string text)

Launcher.Client.Avalonia/GUI/TabButton.cs

@@ -1,11 +1,17 @@
-namespace Launcher.Client.Avalonia.GUI;
+using Avalonia.Styling;
 
-public class TabButton : Button
+namespace Launcher.Client.Avalonia.GUI;
+
+public partial class TabButton : Button, IStyleable
 {
+    Type IStyleable.StyleKey => typeof(Button);
+    
     public static readonly StyledProperty<Grid> TabGridProp = AvaloniaProperty.Register<TabButton, Grid>("TabGrid");
     public Grid TabGrid
     {
         get => GetValue(TabGridProp);
         set => SetValue(TabGridProp, value);
     }
+    
+    public TabButton() :base() {}
 }