diff --git a/Gemfile b/Gemfile
index 93c2052f15f6b5b33f2d9ca1b655e92fbd27c1d2..f43f334c8012fa3c2c2d2300a9f3007e1ba0c58b 100644
--- a/Gemfile
+++ b/Gemfile
@@ -277,6 +277,7 @@ gem 'webpack-rails', '~> 0.9.10'
 gem 'rack-proxy', '~> 0.6.0'
 
 gem 'sass-rails', '~> 5.0.6'
+gem 'sass', '~> 3.5'
 gem 'uglifier', '~> 2.7.2'
 
 gem 'addressable', '~> 2.5.2'
diff --git a/Gemfile.lock b/Gemfile.lock
index 430025c7bdeb56342bb2b4a8f446d79aa21f7210..b9780d4c23fd9f4ee85794b553c47ec0c612a6a3 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1129,6 +1129,7 @@ DEPENDENCIES
   rufus-scheduler (~> 3.4)
   rugged (~> 0.27)
   sanitize (~> 4.6)
+  sass (~> 3.5)
   sass-rails (~> 5.0.6)
   scss_lint (~> 0.56.0)
   seed-fu (~> 2.3.7)
diff --git a/Gemfile.rails4.lock b/Gemfile.rails4.lock
index 9e7bae84299f17ea9bc7a5b15a5c93c6064d18e1..3d81c570b899a458f4a0d9bed2cb922541730f55 100644
--- a/Gemfile.rails4.lock
+++ b/Gemfile.rails4.lock
@@ -1119,6 +1119,7 @@ DEPENDENCIES
   rufus-scheduler (~> 3.4)
   rugged (~> 0.27)
   sanitize (~> 4.6)
+  sass (~> 3.5)
   sass-rails (~> 5.0.6)
   scss_lint (~> 0.56.0)
   seed-fu (~> 2.3.7)