diff --git a/demo.ipynb b/demo.ipynb
index cb8a74d..c00b6d6 100644
--- a/demo.ipynb
+++ b/demo.ipynb
@@ -780,6 +780,23 @@
    "outputs": [],
    "source": [
     "from IPython.display import HTML, display\n",
+    "import base64\n",
+    "import os\n",
+    "\n",
+    "def get_video_base64(video_path):\n",
+    "    \"\"\"\n",
+    "    Reads a local video file and encodes it to a base64 data URI to play in sandboxed Colab iframes.\n",
+    "    \"\"\"\n",
+    "    if not os.path.exists(video_path):\n",
+    "        return \"\"\n",
+    "    try:\n",
+    "        with open(video_path, \"rb\") as f:\n",
+    "            data = f.read()\n",
+    "        b64_str = base64.b64encode(data).decode(\"utf-8\")\n",
+    "        return f\"data:video/mp4;base64,{b64_str}\"\n",
+    "    except Exception as e:\n",
+    "        print(f\"Warning: Failed to encode video {video_path} to base64: {e}\")\n",
+    "        return \"\"\n",
     "\n",
     "def display_comparison(\n",
     "    video_path,\n",
@@ -792,6 +809,13 @@
     "    \"\"\"\n",
     "    Renders a beautifully styled comparison board with local HTML5 video player.\n",
     "    \"\"\"\n",
+    "    video_src = get_video_base64(video_path)\n",
+    "    if not video_src:\n",
+    "        if video_path.startswith((\"http://\", \"https://\")):\n",
+    "            video_src = video_path\n",
+    "        else:\n",
+    "            video_src = f\"https://video2lora.github.io/{video_path}\"\n",
+    "        \n",
     "    html_content = f\"\"\"\n",
     "    <div style=\"font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif; max-width: 900px; margin: 20px auto; color: #1e293b; background-color: #f8fafc; padding: 24px; border-radius: 16px; box-shadow: 0 4px 20px rgba(0,0,0,0.05);\">\n",
     "        \n",
@@ -803,7 +827,7 @@
     "\n",
     "        <!-- Local HTML5 Video Player -->\n",
     "        <div style=\"text-align: center; margin-bottom: 20px; background: #000; border-radius: 12px; overflow: hidden; box-shadow: 0 4px 12px rgba(0,0,0,0.15);\">\n",
-    "            <video src=\"{video_path}\" controls loop muted autoplay style=\"width: 100%; max-height: 400px; object-fit: contain; display: block; margin: 0 auto;\"></video>\n",
+    "            <video src=\"{video_src}\" controls loop muted autoplay style=\"width: 100%; max-height: 400px; object-fit: contain; display: block; margin: 0 auto;\"></video>\n",
     "        </div>\n",
     "        \n",
     "        <!-- Question Prompt Card -->\n",