diff --git a/Gemfile.lock b/Gemfile.lock
index c4062711..323fcd7b 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -177,7 +177,7 @@ GEM
       bigdecimal
       rexml
     crass (1.0.6)
-    css_parser (2.0.0)
+    css_parser (2.1.0)
       addressable
     csv (3.3.5)
     date (3.5.1)