change header background data grid mui

Thu Mar 24 2022 10:40:54 GMT+0000 (Coordinated Universal Time)

Saved by @jacopo

//MUI v5
"& .MuiDataGrid-columnHeaders": {
  backgroundColor: "rgba(0,0,255,0.6)",
  color: "rgba(255,0,0,0.7)",
  fontSize: 16
}