diff --git a/_layouts/post.html b/_layouts/post.html
index 74f182f..e11bed6 100644
--- a/_layouts/post.html
+++ b/_layouts/post.html
@@ -27,4 +27,6 @@ <h1 class="post-title p-name" itemprop="name headline">{{ page.title | escape }}
     <a class="u-url" href="{{ page.url | relative_url }}" hidden></a>
 </article>
 
-{% include mermaid.html %}
\ No newline at end of file
+{% if content contains 'language-mermaid' %}
+{% include mermaid.html %}
+{% endif %}
\ No newline at end of file