diff --git a/lib/integration-guides.tsx b/lib/integration-guides.tsx
index 5cfaf17..dd175f7 100644
--- a/lib/integration-guides.tsx
+++ b/lib/integration-guides.tsx
@@ -2298,15 +2298,32 @@ export default defineConfig({
       <p>Follow these steps to add Pulse through GTM:</p>
       <ol>
         <li>Go to <strong>Tags &rarr; New &rarr; Custom HTML</strong></li>
-        <li>Paste the Pulse script</li>
+        <li>Paste the snippet below (replace <code>your-site.com</code> with your domain)</li>
         <li>Set the trigger to <strong>All Pages</strong></li>
         <li>Publish your container</li>
       </ol>
-      <CodeBlock filename="GTM → Custom HTML Tag">{`<script
+      <CodeBlock filename="GTM → Custom HTML Tag (recommended)">{`<script>
+  window.pulseConfig = { domain: "your-site.com" };
+</script>
+<script defer src="https://pulse.ciphera.net/script.js"></script>`}</CodeBlock>
+
+      <p>
+        This uses a global config object so that GTM does not need to preserve{' '}
+        <code>data-*</code> attributes on the injected script element. You can
+        also pass <code>api</code>, <code>storage</code>, and other options via{' '}
+        <code>pulseConfig</code>.
+      </p>
+
+      <details>
+        <summary className="cursor-pointer text-sm text-neutral-500 dark:text-neutral-400 hover:text-neutral-700 dark:hover:text-neutral-300">
+          Alternative: inline data attributes (may not work in all GTM setups)
+        </summary>
+        <CodeBlock filename="GTM → Custom HTML Tag (alternative)">{`<script
   defer
   data-domain="your-site.com"
   src="https://pulse.ciphera.net/script.js"
 ></script>`}</CodeBlock>
+      </details>
 
       <p>
         For more details, see the{' '}
diff --git a/public/script.js b/public/script.js
index 34f078a..1a15f6d 100644
--- a/public/script.js
+++ b/public/script.js
@@ -19,18 +19,37 @@
   }
 
 
-  // * Get domain from script tag
-  const script = document.currentScript || document.querySelector('script[data-domain]');
-  if (!script || !script.getAttribute('data-domain')) {
+  // * Get config from script tag, or fall back to window.pulseConfig for GTM / tag managers
+  // * GTM Custom HTML tags may not preserve data-* attributes on the injected <script> element,
+  // * so we also search by src URL and support a global config object.
+  const script = document.currentScript
+    || document.querySelector('script[data-domain]')
+    || document.querySelector('script[src*="pulse.ciphera.net/script"]');
+
+  const globalConfig = window.pulseConfig || {};
+
+  // * Helper: read a config value from script data-* attribute or globalConfig
+  function attr(name) {
+    // * Support both "storage-ttl" (data-attr style) and "storageTtl" (camelCase config style)
+    var camel = name.replace(/-([a-z])/g, function(_, c) { return c.toUpperCase(); });
+    return (script && script.getAttribute('data-' + name)) || globalConfig[name] || globalConfig[camel] || null;
+  }
+  function hasAttr(name) {
+    // * Support both "no-scroll" (data-attr style) and "noScroll" (camelCase config style)
+    var camel = name.replace(/-([a-z])/g, function(_, c) { return c.toUpperCase(); });
+    return (script && script.hasAttribute('data-' + name)) || globalConfig[name] === true || globalConfig[camel] === true;
+  }
+
+  const domain = attr('domain');
+  if (!domain) {
     return;
   }
 
-  const domain = script.getAttribute('data-domain');
-  const apiUrl = script.getAttribute('data-api') || 'https://pulse-api.ciphera.net';
+  const apiUrl = attr('api') || 'https://pulse-api.ciphera.net';
   // * Visitor ID storage: "local" (default, cross-tab) or "session" (ephemeral per-tab)
-  const storageMode = (script.getAttribute('data-storage') || 'local').toLowerCase() === 'session' ? 'session' : 'local';
+  const storageMode = (attr('storage') || 'local').toLowerCase() === 'session' ? 'session' : 'local';
   // * When storage is "local", optional TTL in hours; after TTL the ID is regenerated (e.g. 24 = one day)
-  const ttlHours = storageMode === 'local' ? parseFloat(script.getAttribute('data-storage-ttl') || '24') : 0;
+  const ttlHours = storageMode === 'local' ? parseFloat(attr('storage-ttl') || '24') : 0;
   const ttlMs = ttlHours > 0 ? ttlHours * 60 * 60 * 1000 : 0;
 
   let currentEventId = null;
@@ -343,7 +362,7 @@
   // * Auto-track scroll depth at 25%, 50%, 75%, and 100% (on by default)
   // * Each threshold fires once per pageview; resets on SPA navigation
   // * Opt-out: add data-no-scroll to the script tag
-  var trackScroll = !script.hasAttribute('data-no-scroll');
+  var trackScroll = !hasAttr('no-scroll');
 
   if (trackScroll) {
     var scrollThresholds = [25, 50, 75, 100];
@@ -378,8 +397,8 @@
 
   // * Auto-track outbound link clicks and file downloads (on by default)
   // * Opt-out: add data-no-outbound or data-no-downloads to the script tag
-  var trackOutbound = !script.hasAttribute('data-no-outbound');
-  var trackDownloads = !script.hasAttribute('data-no-downloads');
+  var trackOutbound = !hasAttr('no-outbound');
+  var trackDownloads = !hasAttr('no-downloads');
 
   if (trackOutbound || trackDownloads) {
     var FILE_EXT_REGEX = /\.(pdf|zip|gz|tar|xlsx|xls|csv|docx|doc|pptx|ppt|mp4|mp3|wav|avi|mov|exe|dmg|pkg|deb|rpm|iso|7z|rar)($|\?|#)/i;