docs: add css change to remove back button when screen size is reduced (

#3873)

Co-authored-by: Moritz Wiesinger <[email protected]>

docs/assets/stylesheets/home.css

@@ -277,3 +277,9 @@ body {
         flex-direction: row-reverse;
     }
 }
+
+@media only screen and (max-width: 1220px) {
+    .md-nav--primary .md-nav__title .md-nav__icon {
+        display: none !important;
+    } 
+}