Add "Fun" nav tab + /fun/ catalog page with dynamotype trainer

- header.html: new "Fun" nav item between Openings and EEGTalk.
- _pages/fun.md: catalog page for interactive lab tools/demos.
- fun/dynamotype_quiz.html: self-contained browser quiz (172 KB,
  no external deps) for learning seizure dynamotype onset/offset
  patterns, based on Sheckler/Stacey et al's "Dynamotypes for
  Dummies" (eNeuro 2025).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: mb-westover

_includes/header.html

@@ -20,6 +20,7 @@
     <li><a href="{{ site.url }}{{ site.baseurl }}/pictures">Pics</a></li>
     <li><a href="{{ site.url }}{{ site.baseurl }}/resources">Resources</a></li>
     <li><a href="{{ site.url }}{{ site.baseurl }}/openings">Openings</a></li>
+    <li><a href="{{ site.url }}{{ site.baseurl }}/fun">Fun</a></li>
     <li><a href="https://nascimentofabioa.wixsite.com/mysite/">EEGTalk</a></li>
 	  </ul>
 	</div>

_pages/fun.md

@@ -0,0 +1,18 @@
+---
+title: "CDAC - Fun"
+layout: textlay
+excerpt: "Fun and useful interactive tools from the CDAC lab."
+sitemap: false
+permalink: /fun/
+---
+
+# Fun
+
+A small collection of interactive tools, demos, and learning aids built by the lab. Most run entirely in your browser — nothing to install.
+
+### Dynamotype onset/offset trainer
+A quiz tool to help you learn to recognize seizure **dynamotypes** — the characteristic onset and offset patterns of seizures. It drills you on the dynamotype taxonomy from Stacey and colleagues' "Dynamotypes for Dummies" toolbox and atlas.
+
+[**Launch the dynamotype trainer →**]({{ site.url }}{{ site.baseurl }}/fun/dynamotype_quiz.html)
+
+<small>Based on: Sheckler C, Kish K, Walker Z, Barkelew G, Crisp DN, Szuromi MP, Saggio ML, Stacey WC. *Dynamotypes for Dummies: A Toolbox, Atlas, and Tutorial for Simulating a Comprehensive Range of Realistic Synthetic Seizures.* eNeuro. 2025 Oct 23;12(10):ENEURO.0200-25.2025. doi: [10.1523/ENEURO.0200-25.2025](https://doi.org/10.1523/ENEURO.0200-25.2025). PMID: [41027733](https://pubmed.ncbi.nlm.nih.gov/41027733/); PMCID: PMC12549069.</small>