Update app.py

app.py

@@ -1122,18 +1122,19 @@ with gr.Blocks(css=css, js=js, head=head) as demo:
               <a onclick='snapshot();'>Screenshot</a><br/>
               <img src='' id='img_out' onload='var ctxt = document.getElementById(\"cnv_out\").getContext(\"2d\");ctxt.drawImage(this, 0, 0);'/><br/>
               <canvas id='cnv_out'></canvas>
-              <div id='compass_box'><div id='compass'><b style='color:blue;'>◅</b>𝍠<b style='color:red;'>▻</b></div>
-                <a id='fullscreen' style='position:relative;top:2em;' onclick='
+              <div id='compass_box'><div id='compass'><a id='fullscreen' onclick='
                 const model3D = document.getElementById(\"model3D\");
                 if (model3D.style.width != \"100vw\") {
                   model3D.style.width = \"100vw\";
                   model3D.style.height = \"100vh\";
                   model3D.style.position = \"fixed\";
+                  model3D.style.zIndex = \"100\";
                 } else {
                   model3D.style.width = \"initial\";
                   model3D.style.height = \"initial\";
                   model3D.style.position = \"initial\";
-                }'>[+]</a>
+                  model3D.style.zIndex = \"initial\";
+                }'><b style='color:blue;'>◅</b>𝍠<b style='color:red;'>▻</b></a></div>
               </div>
             """)
             render = gr.Button("Render")