https://www.w3schools.com/howto/howto_js_collapsible.asp https://dev.to/guimg/hide-menu-when-scrolling-in-reactjs-47bj NESTED GRID https://www.quackit.com/css/grid/tutorial/create_a_nested_grid.cfm http://jsfiddle.net/shivasaxena/8Z4N4/1/