:root{
  --header: <HEX_HERE>;
}
header.topbar, header[role="banner"]{
  background: var(--header) !important;
  color: #fff !important;
}
#mobile-drawer panel{ background: var(--header) !important; color:#fff }
#mobile-drawer a{ color:#fff }
#mobile-drawer a:hover{ opacity:.9 }