diff --git a/index.html b/index.html
index 882eec90ac014bf0922778e854481538bc45ed27..34755c527d885f3254a69d6d75129b04a65cc062 100644
--- a/index.html
+++ b/index.html
@@ -2,7 +2,7 @@
<html>
<head>
<meta charset="utf-8">
- <script src="http://d3js.org/d3.v7.min.js"></script>
+ <script src="https://d3js.org/d3.v7.min.js"></script>
<script src="script.js"></script>