Discord-History-Tracker/app/Desktop/Main/MainContentScreen.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:main="clr-namespace:DHT.Desktop.Main"
             xmlns:controls="clr-namespace:DHT.Desktop.Main.Controls"
             mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
             x:Class="DHT.Desktop.Main.MainContentScreen">

    <Design.DataContext>
        <main:MainContentScreenModel />
    </Design.DataContext>

    <UserControl.Styles>
        <Style Selector="TabControl ItemsPresenter > WrapPanel">
            <Setter Property="Background" Value="#546A9F" />
        </Style>
        <Style Selector="TabItem">
            <Setter Property="Foreground" Value="#E9E9E9" />
            <Setter Property="FontSize" Value="20" />
        </Style>
        <Style Selector="TabItem[TabStripPlacement=Left] /template/ ContentPresenter#PART_ContentPresenter">
            <Setter Property="Margin" Value="5 0" />
        </Style>
        <Style Selector="TabItem:pointerover">
            <Setter Property="Background" Value="#1F2E45" />
        </Style>
        <Style Selector="TabItem:pointerover /template/ Border">
            <Setter Property="Background" Value="#1F2E45" />
        </Style>
        <Style Selector="TabItem:pointerover > TextBlock">
            <Setter Property="Foreground" Value="#E9E9E9" />
        </Style>
        <Style Selector="TabItem:selected:pointerover /template/ Border">
            <Setter Property="Background" Value="#FFFFFF" />
        </Style>
        <Style Selector="TabItem:selected:pointerover > TextBlock">
            <Setter Property="Foreground" Value="#1A2234" />
        </Style>
        <Style Selector="TabItem:selected">
            <Setter Property="Foreground" Value="#1A2234" />
            <Setter Property="Background" Value="#FFFFFF" />
        </Style>
        <Style Selector="TabItem:selected /template/ Border#PART_SelectedPipe">
            <Setter Property="IsVisible" Value="False" />
        </Style>
        <Style Selector="TabItem:disabled > TextBlock">
            <Setter Property="Foreground" Value="#B2B2B2" />
            <Setter Property="TextDecorations" Value="Strikethrough" />
        </Style>
        <Style Selector="TabItem.first">
            <Setter Property="Margin" Value="0 13 0 0" />
        </Style>
        <Style Selector="TabControl">
            <Setter Property="Padding" Value="0" />
        </Style>
        <Style Selector="ContentPresenter.page">
            <Setter Property="Margin" Value="15 21" />
        </Style>
    </UserControl.Styles>

    <DockPanel>
        <TabControl x:Name="TabControl" TabStripPlacement="Left">
            <TabItem x:Name="TabDatabase" Header="Database" Classes="first">
                <DockPanel>
                    <controls:StatusBar DataContext="{Binding StatusBarModel}" DockPanel.Dock="Bottom" />
                    <ScrollViewer>
                        <ContentPresenter Content="{Binding DatabasePage}" Classes="page" />
                    </ScrollViewer>
                </DockPanel>
            </TabItem>
            <TabItem x:Name="TabTracking" Header="Tracking">
                <DockPanel>
                    <controls:StatusBar DataContext="{Binding StatusBarModel}" DockPanel.Dock="Bottom" />
                    <ScrollViewer>
                        <ContentPresenter Content="{Binding TrackingPage}" Classes="page" />
                    </ScrollViewer>
                </DockPanel>
            </TabItem>
            <TabItem x:Name="TabViewer" Header="Viewer">
                <DockPanel>
                    <controls:StatusBar DataContext="{Binding StatusBarModel}" DockPanel.Dock="Bottom" />
                    <ScrollViewer>
                        <ContentPresenter Content="{Binding ViewerPage}" Classes="page" />
                    </ScrollViewer>
                </DockPanel>
            </TabItem>
        </TabControl>
    </DockPanel>

</UserControl>