matsnackbar background color

1/*In the ts file:*/
2this.snackBar.openFromComponent(SnackComponent, {
3      data: {
4        message: 'Hello, snackbar!'
5      },
6      duration: 2000,
7      panelClass: ['snackbar'] /*This is the class you'll refer to*/
8    });
9/*In the css file:*/
10.snackbar {
11  background: lightgreen;
12}