diff --git a/.github/dependabot.yml b/.github/dependabot.yml
index 5c3a96a..44279c8 100644
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@@ -5,6 +5,9 @@ updates:
     directory: "/"
     schedule:
       interval: weekly
+      day: monday
+      time: "06:00"
+      timezone: "Asia/Tokyo"
     open-pull-requests-limit: 10
     groups:
       # Bundle non-major updates into a single PR to reduce noise
@@ -18,6 +21,9 @@ updates:
     directory: "/"
     schedule:
       interval: weekly
+      day: monday
+      time: "06:00"
+      timezone: "Asia/Tokyo"
     groups:
       github-actions:
         update-types:
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index b1d6e3a..ff7bb0d 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -11,11 +11,9 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - uses: pnpm/action-setup@v4
-        with:
-          version: 11.2.2
+      - uses: pnpm/action-setup@v6
 
-      - uses: actions/setup-node@v4
+      - uses: actions/setup-node@v6
         with:
           node-version: 22
           cache: pnpm
diff --git a/.github/workflows/dependabot-auto-merge.yml b/.github/workflows/dependabot-auto-merge.yml
index 2298fb6..0271dd9 100644
--- a/.github/workflows/dependabot-auto-merge.yml
+++ b/.github/workflows/dependabot-auto-merge.yml
@@ -13,7 +13,7 @@ jobs:
     steps:
       - name: Fetch Dependabot metadata
         id: metadata
-        uses: dependabot/fetch-metadata@21025c705c08248db411dc16f3619e6b5f9ea21a # v2.5.0
+        uses: dependabot/fetch-metadata@25dd0e34f4fe68f24cc83900b1fe3fe149efef98 # v3.1.0
         with:
           github-token: ${{ secrets.GITHUB_TOKEN }}
 
diff --git a/.github/workflows/deploy.yml b/.github/workflows/deploy.yml
index 0b27503..5880f9e 100644
--- a/.github/workflows/deploy.yml
+++ b/.github/workflows/deploy.yml
@@ -3,6 +3,11 @@ name: Deploy to GitHub Pages
 on:
   push:
     branches: [main]
+  schedule:
+    # 毎週月曜 00:00 UTC（= 月曜 09:00 JST）。
+    # GITHUB_TOKEN によるオートマージの push は deploy をトリガーしないため、
+    # Dependabot 週次実行（月曜 06:00 JST）+ オートマージ完了の数時間後にまとめてデプロイする。
+    - cron: "0 0 * * 1"
   workflow_dispatch:
 
 permissions:
@@ -20,11 +25,9 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - uses: pnpm/action-setup@v4
-        with:
-          version: 11.2.2
+      - uses: pnpm/action-setup@v6
 
-      - uses: actions/setup-node@v4
+      - uses: actions/setup-node@v6
         with:
           node-version: 22
           cache: pnpm
@@ -40,9 +43,10 @@ jobs:
       - name: Add .nojekyll
         run: touch out/.nojekyll
 
-      - uses: actions/upload-pages-artifact@v3
+      - uses: actions/upload-pages-artifact@v5
         with:
           path: ./out
+          include-hidden-files: true
 
   deploy:
     needs: build
@@ -53,4 +57,4 @@ jobs:
     steps:
       - name: Deploy to GitHub Pages
         id: deployment
-        uses: actions/deploy-pages@v4
+        uses: actions/deploy-pages@v5
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index b4aa370..b7839c6 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -4,6 +4,9 @@ settings:
   autoInstallPeers: true
   excludeLinksFromLockfile: false
 
+overrides:
+  postcss@<8.5.10: ^8.5.10
+
 importers:
 
   .:
@@ -580,10 +583,6 @@ packages:
   picocolors@1.1.1:
     resolution: {integrity: sha512-xceH2snhtb5M9liqDsmEw56le376mTZkEX/jEb/RxNFyegNul7eNslCXP9FDj/Lcu0X8KEyMceP2ntpaHrDEVA==}
 
-  postcss@8.4.31:
-    resolution: {integrity: sha512-PS08Iboia9mts/2ygV3eLpY5ghnUcfLV/EXTOW1E2qYxJKGGBUtNjN76FYHnMs36RmARn41bC0AZmn+rR0OVpQ==}
-    engines: {node: ^10 || ^12 || >=14}
-
   postcss@8.5.15:
     resolution: {integrity: sha512-FfR8sjd4em2T6fb3I2MwAJU7HWVMr9zba+enmQeeWFfCbm+UOC/0X4DS8XtpUTMwWMGbjKYP7xjfNekzyGmB3A==}
     engines: {node: ^10 || ^12 || >=14}
@@ -1004,7 +1003,7 @@ snapshots:
       '@swc/helpers': 0.5.15
       baseline-browser-mapping: 2.10.31
       caniuse-lite: 1.0.30001793
-      postcss: 8.4.31
+      postcss: 8.5.15
       react: 19.2.6
       react-dom: 19.2.6(react@19.2.6)
       styled-jsx: 5.1.6(react@19.2.6)
@@ -1024,12 +1023,6 @@ snapshots:
 
   picocolors@1.1.1: {}
 
-  postcss@8.4.31:
-    dependencies:
-      nanoid: 3.3.12
-      picocolors: 1.1.1
-      source-map-js: 1.2.1
-
   postcss@8.5.15:
     dependencies:
       nanoid: 3.3.12
diff --git a/pnpm-workspace.yaml b/pnpm-workspace.yaml
index 520eb9a..7438791 100644
--- a/pnpm-workspace.yaml
+++ b/pnpm-workspace.yaml
@@ -1,2 +1,4 @@
 allowBuilds:
   sharp: true
+overrides:
+  postcss@<8.5.10: ^8.5.10