diff --git a/Gemfile.lock b/Gemfile.lock
index 7b0311c..55f444c 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -6,8 +6,8 @@ GEM
       minitest (~> 5.1)
       thread_safe (~> 0.3, >= 0.3.4)
       tzinfo (~> 1.1)
-    addressable (2.6.0)
-      public_suffix (>= 2.0.2, < 4.0)
+    addressable (2.8.1)
+      public_suffix (>= 2.0.2, < 6.0)
     coffee-script (2.4.1)
       coffee-script-source
       execjs
@@ -30,7 +30,7 @@ GEM
     ffi (1.11.1)
     forwardable-extended (2.6.0)
     gemoji (3.0.1)
-    github-pages (198)
+    github-pages (199)
       activesupport (= 4.2.11.1)
       github-pages-health-check (= 1.16.1)
       jekyll (= 3.8.5)
@@ -67,12 +67,12 @@ GEM
       jekyll-theme-time-machine (= 0.1.1)
       jekyll-titles-from-headings (= 0.5.1)
       jemoji (= 0.10.2)
-      kramdown (= 2.3.0)
+      kramdown (= 1.17.0)
       liquid (= 4.0.0)
       listen (= 3.1.5)
       mercenary (~> 0.3)
       minima (= 2.5.0)
-      nokogiri (>= 1.8.5, < 2.0)
+      nokogiri (>= 1.10.4, < 2.0)
       rouge (= 2.2.1)
       terminal-table (~> 1.4)
     github-pages-health-check (1.16.1)
@@ -94,7 +94,7 @@ GEM
       i18n (~> 0.7)
       jekyll-sass-converter (~> 1.0)
       jekyll-watch (~> 2.0)
-      kramdown (~> 2.3)
+      kramdown (~> 1.14)
       liquid (~> 4.0)
       mercenary (~> 0.3.3)
       pathutil (~> 0.9)
@@ -193,7 +193,7 @@ GEM
       gemoji (~> 3.0)
       html-pipeline (~> 2.2)
       jekyll (~> 3.0)
-    kramdown (2.3.0)
+    kramdown (1.17.0)
     liquid (4.0.0)
     listen (3.1.5)
       rb-fsevent (~> 0.9, >= 0.9.4)