Many CSS properties define the top right bottom and left sides of an element. In order to use the shorthand versions of these properties (for example: margin instead of margin-top, padding instead of padding-left), you need to have your numbers in a very specific order.
That order is:
top
right
bottom
left
An easy way to remember this is to think "TRouBLe". If you don't use this order you'll get in "TRouBLe".
