diff --git a/Gemfile b/Gemfile
index 2c29be8..c7e28ff 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,2 +1,2 @@
 source 'https://rubygems.org'
-gem 'sass', '~> 3.4.9'
+gem 'sass', '3.4.13'
diff --git a/Gemfile.lock b/Gemfile.lock
index 53eaf22..979313e 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -7,4 +7,4 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
-  sass (~> 3.4.13)
+  sass (= 3.4.13)
--
libgit2 0.21.2