diff --git a/index.html b/index.html
index cdd86d9..1e41f17 100644
--- a/index.html
+++ b/index.html
@@ -10,7 +10,7 @@
 <script src="https://unpkg.com/prismjs@1.16.0/prism.js"></script>
 <script src="https://unpkg.com/prismjs@1.16.0/components/prism-c.min.js"></script>
 <script src="https://unpkg.com/prismjs@1.16.0/components/prism-cpp.min.js"></script>
-<script src="https://cdn.jsdelivr.net/npm/marked/marked.min.js"></script>
+<script src="https://cdnjs.cloudflare.com/ajax/libs/marked/3.0.0/marked.min.js"></script>
 
 <script>
 chapters =