diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 89f9c70..3b4bd3f 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -13,14 +13,14 @@ jobs:
     strategy:
       matrix:
         include:
-          - os: ubuntu-latest
-            ruby: "3.1"
           - os: ubuntu-latest
             ruby: "3.2"
           - os: ubuntu-latest
             ruby: "3.3"
           - os: ubuntu-latest
             ruby: "3.4"
+          - os: ubuntu-latest
+            ruby: "4.0"
       fail-fast: false
     runs-on: ${{ matrix.os }}
     steps:
diff --git a/google-style.gemspec b/google-style.gemspec
index 1a20495..4dd1bc6 100644
--- a/google-style.gemspec
+++ b/google-style.gemspec
@@ -31,7 +31,7 @@ Gem::Specification.new do |gem|
                        "README.md", "google-style.yml",
                        "lib/google/style/version.rb"]
 
-  gem.required_ruby_version = ">= 3.1.0"
+  gem.required_ruby_version = ">= 3.2.0"
 
   gem.add_dependency "rubocop", "~> 1.76"
 end
diff --git a/google-style.yml b/google-style.yml
index f41ce90..bc0645c 100644
--- a/google-style.yml
+++ b/google-style.yml
@@ -15,7 +15,7 @@
 AllCops:
   NewCops: disable
   SuggestExtensions: false
-  TargetRubyVersion: 3.1
+  TargetRubyVersion: 3.2
 
 Gemspec/AddRuntimeDependency: # new in 1.65                                                                 
   Enabled: true