The page has a basic header, footer, left pane, content pane layout. Use appropriate HTML 5 tags.
Default page content
By default, the left pane shows a field where the user can edit HTML code and click to see that code previewed in the main content pane.
Clicking on the hamburger icon displays the menu.
Hovering over a menu item highlights that item visually. Clicking on an item updates the left pane of the page to show the selected editor.
After a user has clicked a menu link, the page shows the selected editor.