diff --git a/docs/section-6-playground.html b/docs/section-6-playground.html
index ff35cfd5..986542bc 100644
--- a/docs/section-6-playground.html
+++ b/docs/section-6-playground.html
@@ -16,6 +16,7 @@ permalink: playground
   <option value="bash">Bash</option>
   <option value="c">C</option>
   <option value="cpp">C++</option>
+  <option value="c_sharp">C#</option>
   <option value="go">Go</option>
   <option value="html">HTML</option>
   <option value="java">Java</option>