frontend/node_modules/@mui/material/Backdrop/backdropClasses.js

import generateUtilityClasses from '@mui/utils/generateUtilityClasses';
import generateUtilityClass from '@mui/utils/generateUtilityClass';
export function getBackdropUtilityClass(slot) {
  return generateUtilityClass('MuiBackdrop', slot);
}
const backdropClasses = generateUtilityClasses('MuiBackdrop', ['root', 'invisible']);
export default backdropClasses;