diff --git a/Gemfile.lock b/Gemfile.lock
index e96f3d2b..16b22cc6 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -16,7 +16,7 @@ GEM
       console (~> 1.29)
       fiber-annotation
       io-event (~> 1.6, >= 1.6.5)
-    autoprefixer-rails (10.4.19.0)
+    autoprefixer-rails (10.4.21.0)
       execjs (~> 2)
     bigdecimal (3.1.8)
     colorator (1.1.0)
@@ -89,6 +89,10 @@ GEM
       jekyll (>= 3.3, < 5.0)
     jekyll-sass-converter (3.0.0)
       sass-embedded (~> 1.54)
+    jekyll-seo-tag (2.8.0)
+      jekyll (>= 3.8, < 5.0)
+    jekyll-sitemap (1.4.0)
+      jekyll (>= 3.7, < 5.0)
     jekyll-watch (2.2.1)
       listen (~> 3.0)
     json (2.9.0)
@@ -161,6 +165,8 @@ DEPENDENCIES
   jekyll-paginate-v2 (= 3.0.0)
   jekyll-redirect-from
   jekyll-sass-converter (~> 3.0)
+  jekyll-seo-tag
+  jekyll-sitemap
   tzinfo-data
   webrick (~> 1.8)