diff --git a/Gemfile.lock b/Gemfile.lock
index e95adde..d6c1cb5 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -22,6 +22,7 @@ GEM
       coffee-script-source
       execjs
     coffee-script-source (1.7.1)
+    concurrent-ruby (1.1.5)
     diff-lcs (1.2.5)
     dotenv (0.7.0)
     execjs (2.2.1)
@@ -37,19 +38,18 @@ GEM
       multi_json
       sprockets (>= 2.0.3)
       tilt
-    hike (1.2.3)
     i18n (0.6.9)
     json (1.8.1)
     libv8 (3.16.14.7)
     method_source (0.8.2)
     minitest (5.3.3)
-    multi_json (1.9.3)
+    multi_json (1.14.1)
     pg (0.17.1)
     pry (0.9.12.6)
       coderay (~> 1.0)
       method_source (~> 0.8)
       slop (~> 3.4)
-    rack (1.5.2)
+    rack (1.6.12)
     rack-protection (1.5.3)
       rack
     rack-test (0.6.2)
@@ -92,16 +92,13 @@ GEM
     sitemap_generator (5.0.5)
       builder
     slop (3.5.0)
-    sprockets (2.12.1)
-      hike (~> 1.2)
-      multi_json (~> 1.0)
-      rack (~> 1.0)
-      tilt (~> 1.1, != 1.3.0)
-    sprockets-helpers (1.1.0)
-      sprockets (~> 2.0)
-    sprockets-sass (1.2.0)
-      sprockets (~> 2.0)
-      tilt (~> 1.1)
+    sprockets (3.7.2)
+      concurrent-ruby (~> 1.0)
+      rack (> 1, < 3)
+    sprockets-helpers (1.2.1)
+      sprockets (>= 2.2)
+    sprockets-sass (2.0.0.beta2)
+      sprockets (>= 2.0, < 4.0)
     therubyracer (0.12.1)
       libv8 (~> 3.16.14.0)
       ref