diff --git a/Gemfile.lock b/Gemfile.lock
index b354db6..8f6fcf7 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -90,7 +90,8 @@ GEM
     json (2.3.0)
     json-minify (0.0.3)
       json (> 0)
-    kramdown (2.1.0)
+    kramdown (2.3.1)
+      rexml
     kramdown-parser-gfm (1.1.0)
       kramdown (~> 2.0)
     liquid (4.0.3)
@@ -114,6 +115,7 @@ GEM
     rb-fsevent (0.10.3)
     rb-inotify (0.10.0)
       ffi (~> 1.0)
+    rexml (3.2.4)
     rouge (3.14.0)
     safe_yaml (1.0.5)
     sassc (2.2.1)