diff --git a/Gemfile.lock b/Gemfile.lock
index 712ca3f..b1237df 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -159,7 +159,6 @@ GEM
     jekyll-optional-front-matter (0.3.2)
       jekyll (>= 3.0, < 5.0)
     jekyll-paginate (1.1.0)
-    jekyll-postcss (0.5.0)
     jekyll-readme-index (0.3.0)
       jekyll (>= 3.0, < 5.0)
     jekyll-redirect-from (0.16.0)
@@ -279,7 +278,7 @@ GEM
     thread_safe (0.3.6)
     typhoeus (1.4.0)
       ethon (>= 0.9.0)
-    tzinfo (1.2.9)
+    tzinfo (1.2.10)
       thread_safe (~> 0.1)
     unf (0.1.4)
       unf_ext
@@ -294,7 +293,6 @@ PLATFORMS
 DEPENDENCIES
   github-pages
   html-proofer
-  jekyll-postcss
   nokogiri (>= 1.10.4)
 
 BUNDLED WITH