Feat: add details element shortcode (#52)

Author: AlyshaNolan

README.md

@@ -44,6 +44,7 @@ This theme contains the following custom shorcodes:
 **Formatting**:
 
 - collapse.html - Make a collapsible section.
+- details-disclosure.html - Renders information inside a toggleable element (open by default but can be toggled in/out of visibility).
 - comment.html - Insert a comment that won't be rendered at build time.
 - raw-html.html - Insert raw HTML into a markdown doc.
 

layouts/shortcodes/details-disclosure.html

@@ -0,0 +1,5 @@
+{{ $summary := .Get "summary"}} 
+<details open>
+    <summary>{{ $summary }}</summary>
+    {{ .Inner | markdownify }}
+</details>