app-shell: prevent the page from shifting when scrollbars get added

In the non-mobile mode add a padding to the left if there is a scrollbar.

packages/app-shell/src/app-shell.js

@@ -441,6 +441,13 @@ export class AppShell extends ScopedElementsMixin(LitElement) {
                 min-height: 100vh;
             }
 
+            /* Prevent the page shifting when vertical scrollbars get added */
+            @media (min-width: 680px) {
+                #main {
+                    padding-left: calc(100vw - 100%);
+                }
+            }
+
             #main-logo {
                 padding: 0 50px 0 0;
             }