Your own classes prop

Enable users of the components to overrides the internal styles by accepting a class props.
Added in v3.6.0
Every MUI components accepts a classes props that enables you override the internal styles (see MUI's doc).
With TSS you can easily do the same for your components, it's done by merging the internal classes and the one that might have been provided as props.
This is the new way for Overriding styles - classes prop.
// Please use type instead of interface here
type Props = {
//classes?: { foo?: string; bar?: string; };
classes?: Partial<ReturnType<typeof useStyles>["classes"]>;
function MyTestComponentForMergedClassesInternal(props: Props) {
const { classes } = useStyles({ "color": "pink" }, { props });
//NOTE: Only the classes will be read from props,
//you could write { props: { classes: props.classes } } instead of { props }
//and it would work the same.
return (
<div className={classes.foo}>
<span className={classes.bar}>
The background should be green, the box should have a dotted
border and the text should be pink
const useStyles = makeStyles<{ color: string; }>()({
"foo": {
"border": "3px dotted black",
"backgroundColor": "red"
"bar": {
classes={{ "foo": css({ "backgroundColor": "green" }) }}