Hey Jay,
Good question. Your intuition about CSS is correct. However, the actual tile size is determined (by the browser’s rendering engine) based on the sizes of its contents – player photo, name-number ‘heading’, and data table. So to make the tile smaller, you have to go into the stylesheet and change the sizes (height, line-height, font-size, etc, etc, etc) of the various elements to make the tile look the way you want.