You should remove your padding from the left and right completely by deleting it and not just setting it to zero.
Also if you are stuck by a specific step this might make it easier for you to be clear on your question:
Welcome to the community!
I suggest removing the border-styling, as there is not to be any border.
The other should be fine, or you could do it the short way of
padding: and just enter the two different values as the system recognizes the first value as top and bottom and the second value as left and right.