index.html math formulas render problem

docs/index.html

@@ -29,7 +29,7 @@
   </script>
   <!-- CDN files for docsify-katex -->
   <!-- script src="//cdn.jsdelivr.net/npm/docsify-katex@latest/dist/docsify-katex.js"></script> -->
-  <<script src="//cdn.jsdelivr.net/gh/upupming/docsify-katex@latest/dist/docsify-katex.js"></script>
+  <script src="//cdn.jsdelivr.net/gh/upupming/docsify-katex@latest/dist/docsify-katex.js"></script>
   <link rel="stylesheet" href="//cdn.jsdelivr.net/npm/katex@latest/dist/katex.min.css"/>
 
   <!-- Put them above docsify.min.js -->