GlobalProtect-openconnect/gpgui/src/main.tsx

import {
  CssBaseline,
  ThemeProvider,
  createTheme,
  useMediaQuery,
} from "@mui/material";
import React, { useMemo } from "react";
import ReactDOM from "react-dom/client";
import App from "./App";

function Root() {
  const prefersDarkMode = useMediaQuery("(prefers-color-scheme: dark)");
  const theme = useMemo(
    () =>
      createTheme({
        palette: {
          mode: prefersDarkMode ? "dark" : "light",
        },
      }),
    [prefersDarkMode]
  );

  return (
    <React.StrictMode>
      <ThemeProvider theme={theme}>
        <CssBaseline />
        <App />
      </ThemeProvider>
    </React.StrictMode>
  );
}

ReactDOM.createRoot(document.getElementById("root") as HTMLElement).render(
  <Root />
);