Change background color of button via css

I want to change the background color (and other properties) of a via a css class. When I define the background color in my class, it is alway overwritten by rz_buton... class from default-basic.css file. My Buttons are all orange. What have I got to do?
Regards Frank

Try increasing the specificity of your CSS selector or use the !important modifier.

The !import modifier will work for me, Thanks!

But isn't there a possibility to modifythe ...\Radzen.Blazor\css\default.css?