Add a class of mds-page-shell__header--sticky to .mds-page-shell__header to enable the sticky header behavior.

Add a class of mds-page-shell__header--masthead-only to .mds-page-shell__header to add enough top padding to ensure page content starts below the header.

Add a class of mds-page-shell--on-canvas-vertical-navigation to .mds-page-shell to make the hidden menu visible at wide viewports.

Add a class of mds-page-shell__site-navigation--sticky to .mds-page-shell to make the visible hidden menu sticky at wide viewports.