Unable to customise css

[markoberger]

I have installed ver 5 of the FullCalendar for my angular project. Now I want to customize some styles to make it look good and to be style compatible with the rest of the app. I'm using angular 12 and angular-material so bootstrap is out of the question. Now I'm have tried to change the background color of the button.

.fc .fc-button-primary{
  background-color: red; 
}

Nothing happens. I have put this in my.component.ts where I put
Thank you

[acerix]

Please refer to the support page and use Stack Overflow for help. If this is a bug, please supply a runnable, stripped-down demonstration.