[personal opinion] Harlowe’s support for using Markdown to style the page is flaky at best, so I would advised using actual HTML elements instead. For instance the --- markup in your example doesn’t produce a horizontal ruler <hr> element for me in the test project I created.
I would change your header tagged Passage to use a <hr> element like so…
Score: $score
<hr>
… and replace the Header Markup in your Passage with the HTML equivalent…
<h3>Kitchen</h3>
You see blah blah blah...
warning: If you manually add block based HTML elements (like <h1>, <hr>, <p>, or <div>) to a Passage then you will notice an issue that some content will appear instantly while other content will appear using the standard (fade in) transition effect. To overcome this behaviour you need to use CSS like the following within your project’s Story Stylesheet area to change those block based elements to be inline-block based instead.
h3,hr {
display: inline-block;
width: 100%;
}
If you wish to use a block based HTML element that isn’t current in the list of the above (h3,hr) CSS selector then just add the type of the element to the list.
eg. If you want to include both Header 1 and Header 2 you could change the list like so…