Xamarin.Forms-Samples/FormulaOneApp/FormulaOneApp.Classic.Windows/Themes/Hub.xaml

<ResourceDictionary
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">

    <DataTemplate x:Key="HubHeaderDataTemplate">
        <Grid>
            <TextBlock
            Text="{Binding}"
            FontSize="24"/>
        </Grid>
    </DataTemplate>

    <DataTemplate x:Key="HubSectionHeaderDataTemplate">
        <Grid>
            <TextBlock
            Text="{Binding}"
            FontSize="42"/>
        </Grid>
    </DataTemplate>
    
</ResourceDictionary>