What is the proper way to gain control over Markdown font size, codeblock style, etc?

[wellinthatcase]

Within this snippet of markdown for example,

<mdxam:MarkdownScrollViewer xml:space="preserve" 
                            x:Name="MarkdownPeer" Background="Transparent" 
                            VerticalScrollBarVisibility="Hidden"
                            Margin="16,37,0,0" 
                            Visibility="Hidden" 
                            Foreground="#FFF2EEE5" 
                            FontSize="18">
            null
</mdxam:MarkdownScrollViewer>

Programmatically adding markdown, e.g

TextRange rng = new TextRange(
    TextEntry.Document.ContentStart,
    TextEntry.Document.ContentEnd);
    
MarkdownScrollViewer.Markdown = rng.Text; 

Results in inconsistent Markdown. Here's a few things I noticed in my usage:

1. Headers do not conform to the MarkdownScrollViewer's Foreground, thus remain black.
2. Markdown does not conform to MarkdownScrollViewer's Font properties, most notably, font size.
3. Codeblocks also negate MarkdownScrollViewer's properties, and remain independent.
4. Lists seem to form a margin and end up being formatted ~50px to the right of where expected.

This could be a result of my (probably) improper usage. How should we go about controlling styling of the Markdown in further depth?

[whistyun]

MarkdownScrollViewer has MarkdownStyle property. It can change style for each control in Markdown.
Unfortunately, In current version, I don't provide way to apply additional style, so We should set style for all control.

Styles are identified by the type of control and the value of the tag and applied to each control.
For example Heading1/Heading2 is Paragraph which has "Heading1"/"Heading2" tag.

<mdxam:MarkdownScrollViewer xml:space="preserve">

    # Heading 1
    
    ## Heading 2
    
    content

    <mdxam:MarkdownScrollViewer.MarkdownStyle>
        <Style TargetType="FlowDocument">
            <Style.Resources>
                <Style TargetType="Paragraph">
                    <Style.Triggers>
                        <Trigger Property="Tag" Value="Heading1">
                            <Setter Property="FontSize"   Value="42" />
                            <Setter Property="Foreground" Value="Red" />
                            <Setter Property="FontWeight" Value="Light" />
                        </Trigger>

                        <Trigger Property="Tag" Value="Heading2">
                            <Setter Property="FontSize"   Value="20" />
                            <Setter Property="Foreground" Value="Blue" />
                            <Setter Property="FontWeight" Value="Light" />
                        </Trigger>
                    </Style.Triggers>
                </Style>
            </Style.Resources>
        </Style>
    </mdxam:MarkdownScrollViewer.MarkdownStyle>
</mdxam:MarkdownScrollViewer>

If you want to make from the existing style, see Markdown.Style.xaml.

[whistyun]

I forgot Style.Based On property.
We can include the build-in style to custom style.

<mdxam:MarkdownScrollViewer.MarkdownStyle>
    <Style 
        TargetType="FlowDocument"
        BasedOn="{x:Static mdxam:MarkdownStyle.Standard}">
        <Style.Resources>
            <Style TargetType="Paragraph">
                <Setter Property="Margin" Value="4, 2, 0, 6"/>
                <Style.Triggers>
                    <Trigger Property="Tag" Value="Heading1">
                        <Setter Property="FontSize"   Value="42" />
                        <Setter Property="Foreground" Value="Red" />
                        <Setter Property="FontWeight" Value="Light" />
                        <Setter Property="Margin" Value="0"/>
                    </Trigger>
                </Style.Triggers>
            </Style>
        </Style.Resources>
    </Style>
</mdxam:MarkdownScrollViewer.MarkdownStyle>