Border thickness and width / height

If the element has any border or padding, this is then added to the width and height to arrive at the size of the box that’s rendered on the screen.

Border Lines

  border-top: 1px solid #f6f6f6;
  border-bottom: 1px solid #f6f6f6;

Curved Corners

  border: 1px solid #CCC;
  border-radius: 6px 6px 6px 6px;