Grabbed dndbeyond's source code

```
~/go/bin/sourcemapper -output ddb -jsurl https://media.dndbeyond.com/character-app/static/js/main.90aa78c5.js
```

ddb_main/node_modules/@mui/material/Box/boxClasses.js

@@ -0,0 +1,3 @@
+import generateUtilityClasses from '@mui/utils/generateUtilityClasses';
+const boxClasses = generateUtilityClasses('MuiBox', ['root']);
+export default boxClasses;