start of mobile layout

src/public/javascripts/widgets/mobile_layout.js

@@ -0,0 +1,19 @@
+import FlexContainer from "./flex_container.js";
+import NoteTitleWidget from "./note_title.js";
+import NoteDetailWidget from "./note_detail.js";
+import NoteTreeWidget from "./note_tree.js";
+
+export default class MobileLayout {
+    getRootWidget(appContext) {
+        return new FlexContainer('row')
+            .setParent(appContext)
+            .id('root-widget')
+            .css('height', '100vh')
+            .child(new FlexContainer('column')
+                // .child(/* buttons */)
+                .child(new NoteTreeWidget()))
+            .child(new FlexContainer('column')
+                .child(new NoteTitleWidget())
+                .child(new NoteDetailWidget()));
+    }
+}