diff --git a/public/index.html b/public/index.html
index 502a2c8..c3eb8ae 100644
--- a/public/index.html
+++ b/public/index.html
@@ -3,6 +3,11 @@
   <head>
     <meta charset="utf-8">
     <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <% if (process.env.NODE_ENV === "production") { %>
+    <meta http-equiv="Content-Security-Policy" content="default-src 'none'; connect-src *; img-src *; media-src *; manifest-src 'self'; style-src 'self'; script-src 'self'; base-uri 'self';">
+    <% } else { %>
+    <meta http-equiv="Content-Security-Policy" content="default-src 'none'; connect-src *; img-src *; media-src *; manifest-src 'self'; style-src 'self' 'unsafe-inline'; script-src 'self' 'unsafe-eval'; base-uri 'self';">
+    <% } %>
     <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
     <link rel="icon" href="<%= BASE_URL %>icon.svg">
     <link rel=manifest href="<%= BASE_URL %>manifest.webmanifest">
