diff --git a/Gemfile.lock b/Gemfile.lock
index 3f23bd81..7e19781b 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -7,7 +7,7 @@ GEM
       minitest (~> 5.1)
       tzinfo (~> 1.1)
       zeitwerk (~> 2.2, >= 2.2.2)
-    addressable (2.7.0)
+    addressable (2.8.0)
       public_suffix (>= 2.0.2, < 5.0)
     coffee-script (2.4.1)
       coffee-script-source
@@ -16,7 +16,7 @@ GEM
     colorator (1.1.0)
     commonmarker (0.17.13)
       ruby-enum (~> 0.5)
-    concurrent-ruby (1.1.8)
+    concurrent-ruby (1.1.9)
     dnsruby (1.61.5)
       simpleidn (~> 0.1)
     em-websocket (0.5.2)
@@ -31,7 +31,7 @@ GEM
       multipart-post (>= 1.2, < 3)
       ruby2_keywords
     faraday-net_http (1.0.1)
-    ffi (1.15.0)
+    ffi (1.15.3)
     forwardable-extended (2.6.0)
     gemoji (3.0.1)
     github-pages (213)
@@ -196,12 +196,12 @@ GEM
       gemoji (~> 3.0)
       html-pipeline (~> 2.2)
       jekyll (>= 3.0, < 5.0)
-    kramdown (2.3.1)
+    kramdown (2.3.0)
       rexml
     kramdown-parser-gfm (1.1.0)
       kramdown (~> 2.0)
     liquid (4.0.3)
-    listen (3.4.1)
+    listen (3.5.1)
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
     mercenary (0.3.6)
@@ -220,10 +220,10 @@ GEM
       forwardable-extended (~> 2.6)
     public_suffix (4.0.6)
     racc (1.5.2)
-    rb-fsevent (0.10.4)
+    rb-fsevent (0.11.0)
     rb-inotify (0.10.1)
       ffi (~> 1.0)
-    rexml (3.2.4)
+    rexml (3.2.5)
     rouge (3.26.0)
     ruby-enum (0.9.0)
       i18n