classroom.google.com.css

/* class-overlay fix */
[role="menu"]{
  background-color: var(--darkreader-background-fffffff2) !important;
}

/* class-transparency */
.OX4Vcb, nav, .Tabkde, .Aopndd, .RIDjNe, .mwJvDe .KEDCCd{
  background-color: transparent !important;
  border: none !important;
  box-shadow: none !important;
}

/* class-darkreader */
:root{
--darkreader-background-ffffff: transparent !important;
}