Fix unable to click in demo app

Author: Gaurav0

app/styles/app.scss

@@ -33,6 +33,7 @@ body {
 
 #demo-app {
   position: absolute;
+  z-index: -1;
 }
 
 .light-gray {
@@ -227,7 +228,6 @@ body {
   right: 0;
   margin: 0;
   margin-left: 0;
-  z-index: -1;
 
   @media (min-width: $screen-md-min) {
     display: -webkit-flex;