How grid(width card) system divide screen size?

[hamedsbt]

Hello, I can't clearly understand behavior of the grid with card system. How it works?!
How I can limit number of col(card) per row? In other word, Can I define width for each card as percent which it's inside the grid? As such as bootstrap col?!
I'd like to start my new project with AngularDart, But I'm confusing about right choice the proper responsive grid system, can you help me please?
Thank you.