LanMountainDesktop/LanMountainDesktop/Views/SettingsPages/WallpaperSettingsPage.axaml

<UserControl xmlns="https://github.com/avaloniaui"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
             xmlns:ui="using:FluentAvalonia.UI.Controls"
             xmlns:fi="using:FluentIcons.Avalonia"
             xmlns:ic="using:FluentIcons.Avalonia.Fluent"
             xmlns:comp="using:LanMountainDesktop.Views.Components"
             mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="600"
             x:Class="LanMountainDesktop.Views.SettingsPages.WallpaperSettingsPage">
    <Grid x:Name="WallpaperSettingsPanel"
          ColumnDefinitions="*, *"
          RowDefinitions="Auto, *">
        <TextBlock x:Name="WallpaperPanelTitleTextBlock"
                   Grid.Row="0" Grid.Column="0" Grid.ColumnSpan="2"
                   FontSize="28"
                   FontWeight="SemiBold"
                   Foreground="{DynamicResource AdaptiveTextPrimaryBrush}"
                   Margin="0,0,0,24"
                   Text="Personalize Wallpaper" />

        <!-- Left Column: Monitor Preview -->
        <Border x:Name="WallpaperPreviewHost"
                Grid.Row="1" Grid.Column="0"
                Margin="0,0,16,0"
                VerticalAlignment="Stretch"
                HorizontalAlignment="Stretch">
            <!-- Monitor Frame (Bezel) -->
            <Border x:Name="WallpaperPreviewFrame"
                    HorizontalAlignment="Stretch"
                    CornerRadius="28"
                    Background="#FF1A1A1A"
                    Padding="12">
                <Border x:Name="WallpaperPreviewViewport"
                        ClipToBounds="True"
                        CornerRadius="12"
                        Background="#30111827">
                    <Grid>
                        <Image x:Name="WallpaperPreviewVideoImage"
                               IsVisible="False"
                               IsHitTestVisible="False"
                               Stretch="UniformToFill"
                               HorizontalAlignment="Stretch"
                               VerticalAlignment="Stretch" />

                        <Grid x:Name="WallpaperPreviewGrid"
                              HorizontalAlignment="Center"
                              VerticalAlignment="Center">
                            <Border x:Name="WallpaperPreviewTopStatusBarHost"
                                    Grid.Row="0"
                                    Background="Transparent"
                                    Padding="2">
                                <StackPanel x:Name="WallpaperPreviewTopStatusComponentsPanel"
                                            Orientation="Horizontal"
                                            Spacing="3">
                                    <comp:ClockWidget x:Name="WallpaperPreviewClockWidget"
                                                      IsVisible="False" />
                                </StackPanel>
                            </Border>

                            <Border x:Name="WallpaperPreviewBottomTaskbarContainer"
                                    Classes="glass-strong"
                                    Grid.Row="1"
                                    Margin="3"
                                    CornerRadius="16"
                                    Padding="2">
                                <Grid ColumnDefinitions="Auto,*,Auto"
                                      ColumnSpacing="3">
                                    <Border x:Name="WallpaperPreviewTaskbarFixedActionsHost" Grid.Column="0">
                                        <StackPanel x:Name="WallpaperPreviewBackButtonVisual" Orientation="Horizontal" Spacing="3">
                                            <fi:SymbolIcon Classes="icon-s" Symbol="Window" />
                                            <TextBlock x:Name="WallpaperPreviewBackButtonTextBlock" Text="Back to Windows" VerticalAlignment="Center" />
                                        </StackPanel>
                                    </Border>
                                     <StackPanel x:Name="WallpaperPreviewTaskbarDynamicActionsHost"
                                                 Grid.Column="1"
                                                 Orientation="Horizontal"
                                                 HorizontalAlignment="Center"
                                                 Spacing="3" />
                                    <Border x:Name="WallpaperPreviewTaskbarSettingsActionHost" Grid.Column="2">
                                        <StackPanel Orientation="Horizontal" Spacing="3">
                                            <StackPanel x:Name="WallpaperPreviewComponentLibraryVisual" IsVisible="False" Orientation="Horizontal" Spacing="3">
                                                <fi:FluentIcon Classes="icon-s" Icon="Apps" />
                                                <TextBlock x:Name="WallpaperPreviewComponentLibraryTextBlock" Text="Widget library" VerticalAlignment="Center" />
                                            </StackPanel>
                                            <fi:SymbolIcon x:Name="WallpaperPreviewSettingsButtonIcon" Classes="icon-s" Symbol="Settings" />
                                        </StackPanel>
                                    </Border>
                                </Grid>
                            </Border>
                        </Grid>
                    </Grid>
                </Border>
            </Border>
        </Border>

        <!-- Right Column: Settings Content -->
        <StackPanel Grid.Row="1" Grid.Column="1"
                    Margin="16,0,0,0"
                    Spacing="16">
            <StackPanel Spacing="8">
                <TextBlock Text="Preview status" FontSize="12" Foreground="{DynamicResource AdaptiveTextSecondaryBrush}" />
                <TextBlock x:Name="WallpaperPathTextBlock"
                           FontSize="14"
                           FontWeight="Medium"
                           Foreground="{DynamicResource AdaptiveTextPrimaryBrush}"
                           TextTrimming="CharacterEllipsis"
                           Text="No file selected" />
                <TextBlock x:Name="WallpaperStatusTextBlock"
                           FontSize="12"
                           Foreground="{DynamicResource AdaptiveTextMutedBrush}"
                           Text="Ready" />
            </StackPanel>

            <Separator Background="{DynamicResource SurfaceStrokeColorDefaultBrush}" Height="1" Margin="0,8" />

            <TextBlock Text="Choose image or video" FontSize="16" FontWeight="SemiBold" Foreground="{DynamicResource AdaptiveTextPrimaryBrush}" />
            
            <Grid ColumnDefinitions="*, *" ColumnSpacing="12">
                <Button x:Name="PickWallpaperButton"
                        Grid.Column="0"
                        Classes="accent"
                        HorizontalAlignment="Stretch"
                        Padding="0,10"
                        Content="Browse" />
                <Button x:Name="ClearWallpaperButton"
                        Grid.Column="1"
                        HorizontalAlignment="Stretch"
                        Padding="0,10"
                        Content="Reset" />
            </Grid>

            <Border Classes="settings-expander-shell">
<ui:SettingsExpander x:Name="WallpaperPlacementSettingsExpander"
                                                 Header="Placement"
                                                 Padding="12,8">
                <ui:SettingsExpander.Footer>
                    <ComboBox x:Name="WallpaperPlacementComboBox"
                              Width="120">
                        <ComboBoxItem Content="Fill" />
                        <ComboBoxItem Content="Fit" />
                        <ComboBoxItem Content="Stretch" />
                        <ComboBoxItem Content="Center" />
                        <ComboBoxItem Content="Tile" />
                    </ComboBox>
                </ui:SettingsExpander.Footer>
            </ui:SettingsExpander>
            </Border>
        </StackPanel>
    </Grid>
</UserControl>