diff --git a/docs/Gemfile.lock b/docs/Gemfile.lock
index ca566f1..882eb68 100644
--- a/docs/Gemfile.lock
+++ b/docs/Gemfile.lock
@@ -224,7 +224,8 @@ GEM
     rb-fsevent (0.11.1)
     rb-inotify (0.10.1)
       ffi (~> 1.0)
-    rexml (3.2.5)
+    rexml (3.3.6)
+      strscan
     rouge (3.26.0)
     rubyzip (2.3.0)
     safe_yaml (1.0.5)
@@ -238,6 +239,7 @@ GEM
       faraday (> 0.8, < 2.0)
     simpleidn (0.1.1)
       unf (~> 0.1.4)
+    strscan (3.1.0)
     terminal-table (1.8.0)
       unicode-display_width (~> 1.1, >= 1.1.1)
     thread_safe (0.3.6)