[voidcannon] fix code snippet expanding

content/articles/playground/content.md

@@ -22,6 +22,10 @@ Voidcannon supports ||spoiler|| syntax to hide text until the user manually reve
 ||Spoilers will cover everything within them (i.e :p3smile:) but will not visually adapt their height to them
 (due to the way they're made).||
 
+```md
+Voidcannon supports ||spoiler|| syntax to hide text until the user manually reveals it.
+```
+
 ## Media Player Playground
 
 The media player allows playback of YouTube videos.
@@ -728,15 +732,37 @@ message TrackInfoResponse {
 ## HTML
 
 <p>This is some HTML text.</p>
-<marquee>Test</marquee>
-<voidcannon-cta style="margin-top: 1em;">
+<div>
+  <button>This is a button.</button>
+</div>
+
+```html
+<p>This is some HTML text.</p>
+<div>
+  <button>This is a button.</button>
+</div>
+```
+
+HTML in markdown can also include templates that get server-rendered.
+
+<voidcannon-cta layout="button" style="margin-top: 1em;">
     <md-icon slot="icon">convert_to_text</md-icon>
     this is a cta rendered from a markdown document
-    <button slot="button">pluh</button>
+    <md-filled-button slot="button">pluh</md-filled-button>
 </voidcannon-cta>
 <br>
 <hr>
 
+```html
+<voidcannon-cta layout="button" style="margin-top: 1em;">
+    <md-icon slot="icon">convert_to_text</md-icon>
+    this is a cta rendered from a markdown document
+    <md-filled-button slot="button">pluh</md-filled-button>
+</voidcannon-cta>
+<br>
+<hr>
+```
+
 ## Line Breaks
 
 This is a line.<br>