window object does weird things, rename root ID

when used with (window as any).app, it uses the element with id #app instead

src/scss/global.scss

@@ -8,7 +8,7 @@ body {
     overscroll-behavior-y: contain;
 }
 
-#app {
+#app-root {
     background: var(--body-background-fill);
 }