.header-menu{
  display:none;
  position:fixed;
  top:0;
  left:0;
  /* Use viewport units so the menu covers the full screen on mobile */
  width:100vw;
  height:100vh;
  overflow-y:auto;
  z-index:1000;
  background-color:white;
}
.header-menu.open{display:block;}
.header-menu-nav-folder{display:none;}
.header-menu-nav-folder[data-folder="root"]{display:block;}