Why does CSS not support negative padding?

Question

I have seen this many a times that the prospect of a negative padding might help the development of CSS of certain page elements become better and easier. Yet, there is no p

Answer 1

This could help, by the way:

The box-sizing CSS property is used to alter the default CSS box model used to calculate widths and heights of elements.

http://www.w3.org/TR/css3-ui/#box-sizing
https://developer.mozilla.org/En/CSS/Box-sizing