Width & Height 100% ?

Question

As the title says, can you actually set 100% in both to make it always 100% of the user screen?
Or can you only pick one of them ?

Answer 1

You can do both

Answer 2

And I also figured it's decraped as you can use background-size:cover; thanks though Jafca

Answer 3

You can set both width and height as percentage