diff --git a/demo/public/tumblr-embed.js b/demo/public/tumblr-embed.js
new file mode 100644
index 0000000..a12808c
--- /dev/null
+++ b/demo/public/tumblr-embed.js
@@ -0,0 +1,69 @@
+/**
+ * Speed-Read Tumblr Embed
+ *
+ * Automatically replaces links pointing to the speed-read embed page
+ * with inline <speed-reader> components.
+ *
+ * Theme setup — add both script tags before </body> in your Tumblr theme:
+ *
+ *   <script src="https://cdn.jsdelivr.net/npm/@entrolution/speed-read@latest"></script>
+ *   <script src="https://entrolution.github.io/speed-read/tumblr-embed.js"></script>
+ *
+ * Post usage — in the post HTML, add a plain link:
+ *
+ *   <a href="https://entrolution.github.io/speed-read/embed.html?tumblr=TUMBLR_URL">Read</a>
+ *
+ * Supported query parameters:
+ *   src            - URL to an EPUB, PDF, or CBZ file
+ *   tumblr         - Tumblr post URL
+ *   tumblr-proxy   - Custom CORS proxy URL
+ *   tumblr-playlist - Google Docs playlist URL
+ *   manifest       - chapters.json manifest URL
+ *   height         - Reader height (default: 600px)
+ */
+(function () {
+  var EMBED_PATH = '/speed-read/embed.html';
+  var ATTRS = ['src', 'tumblr', 'tumblr-proxy', 'tumblr-playlist', 'manifest'];
+
+  function init() {
+    var links = document.querySelectorAll('a[href*="' + EMBED_PATH + '"]');
+
+    for (var i = 0; i < links.length; i++) {
+      var link = links[i];
+      try {
+        var url = new URL(link.href);
+        var params = url.searchParams;
+
+        var hasContent = ATTRS.some(function (attr) {
+          return params.has(attr);
+        });
+        if (!hasContent) continue;
+
+        var container = document.createElement('div');
+        container.style.height = params.get('height') || '600px';
+        container.style.width = '100%';
+        container.style.margin = '1em 0';
+
+        var reader = document.createElement('speed-reader');
+        reader.style.width = '100%';
+        reader.style.height = '100%';
+
+        for (var j = 0; j < ATTRS.length; j++) {
+          var value = params.get(ATTRS[j]);
+          if (value) reader.setAttribute(ATTRS[j], value);
+        }
+
+        container.appendChild(reader);
+        link.parentNode.replaceChild(container, link);
+      } catch (e) {
+        // leave the link alone if URL parsing fails
+      }
+    }
+  }
+
+  if (document.readyState === 'loading') {
+    document.addEventListener('DOMContentLoaded', init);
+  } else {
+    init();
+  }
+})();