LanMountainDesktop/LanMountainDesktop/Styles/NavigationStyles.axaml

<Styles xmlns="https://github.com/avaloniaui"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:ui="using:FluentAvalonia.UI.Controls"
        xmlns:fi="using:FluentIcons.Avalonia.Fluent">

    <Styles.Resources>
        <x:Double x:Key="PaneToggleButtonWidth">40</x:Double>
        <x:Double x:Key="PaneToggleButtonHeight">40</x:Double>
        <x:Double x:Key="NavigationViewItemIconBoxHeight">20</x:Double>
        <GridLength x:Key="PaneToggleButtonHeightGridLength">40</GridLength>
    </Styles.Resources>

    <Style Selector="Button.pane-toggle-button">
        <Setter Property="Width" Value="{DynamicResource PaneToggleButtonWidth}" />
        <Setter Property="Height" Value="{DynamicResource PaneToggleButtonHeight}" />
        <Setter Property="Padding" Value="0" />
        <Setter Property="Background" Value="Transparent" />
        <Setter Property="BorderThickness" Value="0" />
        <Setter Property="CornerRadius" Value="{DynamicResource ControlCornerRadius}" />
        <Setter Property="VerticalAlignment" Value="Center" />
        <Setter Property="HorizontalAlignment" Value="Center" />
        <Setter Property="Template">
            <ControlTemplate>
                <Border x:Name="LayoutRoot"
                        Background="{TemplateBinding Background}"
                        CornerRadius="{TemplateBinding CornerRadius}">
                    <Border.Transitions>
                        <Transitions>
                            <BrushTransition Property="Background" Duration="0:0:0.083" Easing="0.05,0.75,0.10,1.00" />
                        </Transitions>
                    </Border.Transitions>
                    <Grid x:Name="ContentRoot"
                          ColumnDefinitions="Auto,*">
                        <Grid.RowDefinitions>
                            <RowDefinition Height="{DynamicResource PaneToggleButtonHeightGridLength}" />
                        </Grid.RowDefinitions>

                        <Border Width="{TemplateBinding Width}">
                            <ContentPresenter x:Name="IconPresenter"
                                              HorizontalAlignment="Center"
                                              VerticalAlignment="Center"
                                              Content="{TemplateBinding Content}" />
                        </Border>

                        <ContentPresenter x:Name="ContentPresenter"
                                          VerticalContentAlignment="Center"
                                          Content="{TemplateBinding Tag}"
                                          FontSize="{TemplateBinding FontSize}"
                                          Padding="4,0,0,0"
                                          Grid.Column="1" />
                    </Grid>
                </Border>
            </ControlTemplate>
        </Setter>
    </Style>

    <Style Selector="Button.pane-toggle-button:pointerover /template/ Border#LayoutRoot">
        <Setter Property="Background" Value="{DynamicResource SubtleFillColorSecondaryBrush}" />
    </Style>

    <Style Selector="Button.pane-toggle-button:pressed /template/ Border#LayoutRoot">
        <Setter Property="Background" Value="{DynamicResource SubtleFillColorTertiaryBrush}" />
    </Style>

    <Style Selector="Button.nav-back">
        <Setter Property="Width" Value="{DynamicResource PaneToggleButtonWidth}" />
        <Setter Property="Height" Value="{DynamicResource PaneToggleButtonHeight}" />
        <Setter Property="Padding" Value="0" />
        <Setter Property="Background" Value="Transparent" />
        <Setter Property="BorderThickness" Value="0" />
        <Setter Property="CornerRadius" Value="{DynamicResource ControlCornerRadius}" />
        <Setter Property="VerticalAlignment" Value="Center" />
        <Setter Property="HorizontalAlignment" Value="Center" />
        <Setter Property="Template">
            <ControlTemplate>
                <Border x:Name="LayoutRoot"
                        Background="{TemplateBinding Background}"
                        CornerRadius="{TemplateBinding CornerRadius}">
                    <Border.Transitions>
                        <Transitions>
                            <BrushTransition Property="Background" Duration="0:0:0.083" Easing="0.05,0.75,0.10,1.00" />
                        </Transitions>
                    </Border.Transitions>
                    <Grid x:Name="ContentRoot"
                          ColumnDefinitions="Auto,*">
                        <Grid.RowDefinitions>
                            <RowDefinition Height="{DynamicResource PaneToggleButtonHeightGridLength}" />
                        </Grid.RowDefinitions>

                        <Border Width="{TemplateBinding Width}">
                            <fi:FluentIcon Icon="ChevronLeft"
                                           IconVariant="Regular"
                                           FontSize="16"
                                           HorizontalAlignment="Center"
                                           VerticalAlignment="Center" />
                        </Border>

                        <ContentPresenter x:Name="ContentPresenter"
                                          VerticalContentAlignment="Center"
                                          Content="{TemplateBinding Content}"
                                          FontSize="{TemplateBinding FontSize}"
                                          Padding="4,0,0,0"
                                          Grid.Column="1" />
                    </Grid>
                </Border>
            </ControlTemplate>
        </Setter>
    </Style>

    <Style Selector="Button.nav-back:pointerover /template/ Border#LayoutRoot">
        <Setter Property="Background" Value="{DynamicResource SubtleFillColorSecondaryBrush}" />
    </Style>

    <Style Selector="Button.nav-back:pressed /template/ Border#LayoutRoot">
        <Setter Property="Background" Value="{DynamicResource SubtleFillColorTertiaryBrush}" />
    </Style>

    <Style Selector="ui|NavigationView.settings-navigation-view">
        <Setter Property="Transitions">
            <Transitions>
                <DoubleTransition Property="Opacity" Duration="0:0:0.2" Easing="0.05,0.75,0.10,1.00" />
            </Transitions>
        </Setter>
    </Style>

    <Style Selector="ui|NavigationView.settings-navigation-view /template/ Border#NavigationViewBorder">
        <Setter Property="Transitions">
            <Transitions>
                <BrushTransition Property="Background" Duration="0:0:0.167" Easing="0.05,0.75,0.10,1.00" />
            </Transitions>
        </Setter>
    </Style>

    <Style Selector="ui|NavigationViewItem.settings-nav-item">
        <Setter Property="Transitions">
            <Transitions>
                <BrushTransition Property="Background" Duration="0:0:0.083" Easing="0.05,0.75,0.10,1.00" />
                <TransformOperationsTransition Property="RenderTransform" Duration="0:0:0.083" Easing="0.05,0.75,0.10,1.00" />
            </Transitions>
        </Setter>
    </Style>

    <Style Selector="ui|NavigationViewItem.settings-nav-item:pointerover">
        <Setter Property="RenderTransform" Value="scale(1.01)" />
    </Style>

    <Style Selector="ui|NavigationViewItem.settings-nav-item:pressed">
        <Setter Property="RenderTransform" Value="scale(0.99)" />
    </Style>

</Styles>