diff --git a/app.py b/app.py
index be99773..ae84a5f 100644
--- a/app.py
+++ b/app.py
@@ -101,7 +101,7 @@ csrf.init_app(app)
 csp = {
     "default-src": "'self'",
     "script-src": "'self'",  # to use nonce
-    "style-src": "'unsafe-inline'",  # for old browsers without support style-src-attr
+    "style-src": ["'self'", "'unsafe-inline'"],
     "base-uri": "'none'",
     "object-src" : "'none'",
 }