adding video

app.py

@@ -16,6 +16,16 @@ _HEADER_ = '''
 <h2>Toon3D: Seeing Cartoons from a New Perspective</h2>
 Toon3D lifts hand-drawn images to 3D with a piecewise-rigid deformation optimization at hand-labeled keypoints and using monocular depth as a prior. The project page is at <a href='https://toon3d.studio/' target='_blank'>https://toon3d.studio/</a> and the Toon3D Labeler is at <a href='https://labeler.toon3d.studio/' target='_blank'>https://labeler.toon3d.studio/</a>. Follow the steps below to run Toon3D!
 
+<div style="text-align: center;">
+    <div id="demoVideo" style="display:block; max-width:640px; margin:auto;">
+        <p>Here is a video for how to use our demo:</p>
+        <video width="100%" height="auto" controls autoplay muted>
+            <source src="https://toon3d.studio/static/assets/toon3d-demo.mp4" type="video/mp4">
+            Your browser does not support the video tag.
+        </video>
+    </div>
+</div>
+
 <div style="margin-top: 20px; font-size: 16px; line-height: 1.6;">
     <div style="display: flex; justify-content: space-between;">
         <div style="width: 49%;">