diff --git a/client/index.html b/client/index.html
index d4abb50..c38c071 100644
--- a/client/index.html
+++ b/client/index.html
@@ -8,7 +8,7 @@
     <meta name="description" content="">
     <meta name="viewport" content="width=device-width, initial-scale=1">
     <!-- css files -->
-    <link rel="stylesheet" href="https://npmcdn.com/github-markdown-css@2.3.0">
+    <link rel="stylesheet" href="https://unpkg.com/github-markdown-css@2.3.0">
     <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/animate.css/3.5.2/animate.min.css">
     <style>
       .markdown-body {
diff --git a/index.ejs.html b/index.ejs.html
index 2ccca11..a2c75cd 100644
--- a/index.ejs.html
+++ b/index.ejs.html
@@ -8,7 +8,7 @@
     <meta name="viewport" content="width=device-width, initial-scale=1">
     <!-- css files -->
     <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/normalize/4.2.0/normalize.min.css">
-    <link rel="stylesheet" href="https://npmcdn.com/github-markdown-css@2.3.0">
+    <link rel="stylesheet" href="https://unpkg.com/github-markdown-css@2.3.0">
     <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/animate.css/3.5.2/animate.min.css">
     <link rel="stylesheet" href="/css/style.css">
     <style>