Wino-Mail/Wino.Calendar/Controls/CalendarItemControl.xaml

<UserControl
    x:Class="Wino.Calendar.Controls.CalendarItemControl"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:helpers="using:Wino.Helpers"
    xmlns:local="using:Wino.Calendar.Controls"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    d:DesignHeight="300"
    d:DesignWidth="400"
    mc:Ignorable="d">

    <Grid
        x:Name="MainGrid"
        BorderBrush="{ThemeResource CalendarSeperatorBrush}"
        BorderThickness="1"
        CornerRadius="6">
        <Grid x:Name="MainBackground" Background="{x:Bind helpers:XamlHelpers.GetSolidColorBrushFromHex(CalendarItem.AssignedCalendar.BackgroundColorHex), Mode=OneWay}" />
        <TextBlock
            x:Name="EventTitleTextblock"
            Margin="2,0"
            HorizontalAlignment="Center"
            VerticalAlignment="Center"
            CharacterSpacing="8"
            FontSize="13"
            FontWeight="SemiBold"
            Foreground="{x:Bind helpers:XamlHelpers.GetReadableTextColor(CalendarItem.AssignedCalendar.BackgroundColorHex), Mode=OneWay}"
            Text="{x:Bind CalendarItem.Title}"
            TextWrapping="Wrap" />

        <VisualStateManager.VisualStateGroups>
            <VisualStateGroup x:Name="EventDurationStates">
                <VisualState x:Name="RegularEvent" />
                <VisualState x:Name="AllDayEvent">
                    <VisualState.Setters>
                        <Setter Target="MainGrid.MinHeight" Value="25" />
                        <Setter Target="EventTitleTextblock.Margin" Value="6,0" />
                    </VisualState.Setters>
                </VisualState>

                <VisualState x:Name="MultiDayEvent">
                    <VisualState.Setters>
                        <Setter Target="MainBackground.Opacity" Value="0.6" />
                        <Setter Target="MainGrid.CornerRadius" Value="0" />
                        <Setter Target="MainGrid.BorderThickness" Value="0.5" />
                    </VisualState.Setters>
                </VisualState>
            </VisualStateGroup>
        </VisualStateManager.VisualStateGroups>
    </Grid>
</UserControl>