diff --git a/README.md b/README.md
index 50e7888..f645f1c 100644
--- a/README.md
+++ b/README.md
@@ -47,3 +47,11 @@ and native GitHub squash auto-merge. Sensitive changes remain manual-only.
 [Setup, required checks, trust assumptions and first-run procedure](docs/guarded-auto-merge.md)
 include the required OpenAI key, branch protection and downstream deployment-event
 limitation. Repository settings and production are not changed by installing it.
+
+### Shared asset cache versions
+
+After changing `script.js` or `style.css`, run `npm run assets:version` and commit
+the updated HTML files with the asset changes. Each page uses a content-derived
+query parameter so browsers and Cloudflare request the matching release assets.
+The test suite rejects missing or stale versions. This does not change the
+protected deployment process or require a Cloudflare cache purge.
diff --git a/cancel.html b/cancel.html
index 94c7d12..1894b9c 100644
--- a/cancel.html
+++ b/cancel.html
@@ -11,7 +11,7 @@
   <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
   <link href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap" rel="stylesheet">
 
-  <link rel="stylesheet" href="style.css">
+  <link rel="stylesheet" href="style.css?v=8287724f17f5">
   <link rel="icon" href="favicon.png" type="image/png">
 </head>
 <body>
diff --git a/computer-help-henderson.html b/computer-help-henderson.html
index f18a60a..67c6880 100644
--- a/computer-help-henderson.html
+++ b/computer-help-henderson.html
@@ -13,7 +13,7 @@
   <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
   <link href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap" rel="stylesheet">
 
-  <link rel="stylesheet" href="style.css">
+  <link rel="stylesheet" href="style.css?v=8287724f17f5">
   <link rel="icon" href="favicon.png" type="image/png">
   <link rel="icon" href="favicon.png" type="image/png" sizes="32x32">
 
@@ -138,6 +138,6 @@ <h4 class="footer-title">Support</h4>
     </div>
   </footer>
 
-  <script src="/script.js" defer></script>
+  <script src="/script.js?v=fb2d384af22c" defer></script>
 </body>
 </html>
diff --git a/custom-pc-builds-henderson.html b/custom-pc-builds-henderson.html
index 30d5954..7d093a9 100644
--- a/custom-pc-builds-henderson.html
+++ b/custom-pc-builds-henderson.html
@@ -13,7 +13,7 @@
   <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
   <link href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap" rel="stylesheet">
 
-  <link rel="stylesheet" href="style.css">
+  <link rel="stylesheet" href="style.css?v=8287724f17f5">
   <link rel="icon" href="favicon.png" type="image/png">
   <link rel="icon" href="favicon.png" type="image/png" sizes="32x32">
 
@@ -138,6 +138,6 @@ <h4 class="footer-title">Support</h4>
     </div>
   </footer>
 
-  <script src="/script.js" defer></script>
+  <script src="/script.js?v=fb2d384af22c" defer></script>
 </body>
 </html>
diff --git a/index.html b/index.html
index 807ebea..3d226ad 100644
--- a/index.html
+++ b/index.html
@@ -13,7 +13,7 @@
   <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
   <link href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap" rel="stylesheet">
 
-  <link rel="stylesheet" href="style.css">
+  <link rel="stylesheet" href="style.css?v=8287724f17f5">
   <link rel="icon" href="favicon.png" type="image/png">
   <link rel="icon" href="favicon.png" type="image/png" sizes="32x32">
 
@@ -669,6 +669,6 @@ <h4 class="footer-title">Support</h4>
     </div>
   </footer>
 
-  <script src="script.js" defer></script>
+  <script src="script.js?v=fb2d384af22c" defer></script>
 </body>
 </html>
diff --git a/package.json b/package.json
index 2959e0a..145e6cb 100644
--- a/package.json
+++ b/package.json
@@ -4,6 +4,7 @@
   "description": "Dex Tech - Henderson NV Tech Support Website",
   "main": "server.js",
   "scripts": {
+    "assets:version": "node scripts/version-static-assets.js",
     "test": "node --test test/*.test.js",
     "start": "node server.js",
     "dev": "node --watch server.js",
diff --git a/privacy.html b/privacy.html
index fbd1a0d..903ef33 100644
--- a/privacy.html
+++ b/privacy.html
@@ -9,7 +9,7 @@
   <link rel="preconnect" href="https://fonts.googleapis.com">
   <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
   <link href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap" rel="stylesheet">
-  <link rel="stylesheet" href="style.css">
+  <link rel="stylesheet" href="style.css?v=8287724f17f5">
   <link rel="icon" href="favicon.png" type="image/png">
   <style>
     .legal-hero {
diff --git a/scripts/version-static-assets.js b/scripts/version-static-assets.js
new file mode 100644
index 0000000..e344fc0
--- /dev/null
+++ b/scripts/version-static-assets.js
@@ -0,0 +1,15 @@
+// Refresh HTML cache keys after editing shared CSS or JavaScript.
+const fs = require('node:fs');
+const path = require('node:path');
+const { createHash } = require('node:crypto');
+const root = path.resolve(__dirname, '..');
+const versions = Object.fromEntries(['style.css', 'script.js'].map(file => [
+  file, createHash('sha256').update(fs.readFileSync(path.join(root, file))).digest('hex').slice(0, 12),
+]));
+for (const file of fs.readdirSync(root).filter(file => file.endsWith('.html'))) {
+  const location = path.join(root, file);
+  const original = fs.readFileSync(location, 'utf8');
+  const updated = original.replace(/(\b(?:src|href)=["'])(\/?)(style\.css|script\.js)(?:\?[^"']*)?(["'])/g,
+    (_, prefix, slash, asset, quote) => `${prefix}${slash}${asset}?v=${versions[asset]}${quote}`);
+  if (updated !== original) fs.writeFileSync(location, updated);
+}
diff --git a/small-business-tech-support-henderson.html b/small-business-tech-support-henderson.html
index 4366217..adce6f5 100644
--- a/small-business-tech-support-henderson.html
+++ b/small-business-tech-support-henderson.html
@@ -13,7 +13,7 @@
   <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
   <link href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap" rel="stylesheet">
 
-  <link rel="stylesheet" href="style.css">
+  <link rel="stylesheet" href="style.css?v=8287724f17f5">
   <link rel="icon" href="favicon.png" type="image/png">
   <link rel="icon" href="favicon.png" type="image/png" sizes="32x32">
 
@@ -138,6 +138,6 @@ <h4 class="footer-title">Support</h4>
     </div>
   </footer>
 
-  <script src="/script.js" defer></script>
+  <script src="/script.js?v=fb2d384af22c" defer></script>
 </body>
 </html>
diff --git a/support.html b/support.html
index fd8bb15..f51e922 100644
--- a/support.html
+++ b/support.html
@@ -11,7 +11,7 @@
   <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
   <link href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap" rel="stylesheet">
   
-  <link rel="stylesheet" href="style.css">
+  <link rel="stylesheet" href="style.css?v=8287724f17f5">
   <link rel="icon" href="favicon.png" type="image/png">
 </head>
 <body>
@@ -167,6 +167,6 @@ <h3>Solana</h3>
     </div>
   </footer>
 
-  <script src="script.js" defer></script>
+  <script src="script.js?v=fb2d384af22c" defer></script>
 </body>
 </html>
diff --git a/terms.html b/terms.html
index 746da22..2c23381 100644
--- a/terms.html
+++ b/terms.html
@@ -9,7 +9,7 @@
   <link rel="preconnect" href="https://fonts.googleapis.com">
   <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
   <link href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap" rel="stylesheet">
-  <link rel="stylesheet" href="style.css">
+  <link rel="stylesheet" href="style.css?v=8287724f17f5">
   <link rel="icon" href="favicon.png" type="image/png">
   <style>
     .legal-hero {
diff --git a/test/static-assets.test.js b/test/static-assets.test.js
new file mode 100644
index 0000000..0aedd1f
--- /dev/null
+++ b/test/static-assets.test.js
@@ -0,0 +1,25 @@
+const assert = require('node:assert/strict');
+const fs = require('node:fs');
+const path = require('node:path');
+const { createHash } = require('node:crypto');
+const { test } = require('node:test');
+const { JSDOM } = require('jsdom');
+const root = path.resolve(__dirname, '..');
+
+test('every shared script and stylesheet URL identifies the current asset content', () => {
+  let references = 0;
+  for (const file of fs.readdirSync(root).filter(file => file.endsWith('.html'))) {
+    const dom = new JSDOM(fs.readFileSync(path.join(root, file), 'utf8'), { url: 'https://dextech.cloud/' });
+    for (const element of dom.window.document.querySelectorAll('script[src], link[rel="stylesheet"][href]')) {
+      const url = new URL(element.src || element.href);
+      if (url.origin !== 'https://dextech.cloud') continue;
+      const asset = url.pathname.slice(1);
+      if (!['style.css', 'script.js'].includes(asset)) continue;
+      const version = createHash('sha256').update(fs.readFileSync(path.join(root, asset))).digest('hex').slice(0, 12);
+      assert.equal(url.searchParams.get('v'), version, `${file}: run npm run assets:version after editing ${asset}`);
+      references++;
+    }
+    dom.window.close();
+  }
+  assert.ok(references >= 10, 'Must check the shared assets across the public site');
+});
diff --git a/wifi-setup-henderson.html b/wifi-setup-henderson.html
index 5630099..e44eb25 100644
--- a/wifi-setup-henderson.html
+++ b/wifi-setup-henderson.html
@@ -13,7 +13,7 @@
   <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
   <link href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap" rel="stylesheet">
 
-  <link rel="stylesheet" href="style.css">
+  <link rel="stylesheet" href="style.css?v=8287724f17f5">
   <link rel="icon" href="favicon.png" type="image/png">
   <link rel="icon" href="favicon.png" type="image/png" sizes="32x32">
 
@@ -138,6 +138,6 @@ <h4 class="footer-title">Support</h4>
     </div>
   </footer>
 
-  <script src="/script.js" defer></script>
+  <script src="/script.js?v=fb2d384af22c" defer></script>
 </body>
 </html>
