CSS 3 Gradient n pixels bottom - Webkit / Safari

Question

Is there a way to create a gradient with a stop of n pixels from the bottom edge of an element?

For example, with Moz / Firefox, it would look like this:

-moz-linear-gradient(center bottom , #f00 2%, #d00 31px)

It should also be noted that this gradient has an accompanying gradient to do the same at the very top of the window. So really css looks like this for FF, and I need to play for webkit:

background-image:
      -moz-linear-gradient(center top , rgba(255,0,0,0.75) 2%, rgba(255,0,0,0) 31px), 
      -moz-linear-gradient(center bottom , rgba(255,0,0,0.75) 2%, rgba(255,0,0,0) 31px);

Answer 1

webkit. ! -webkit-linear-gradient ( webkit), -moz . CSS3, -webkit -moz. ( -webkit-gradient , .)

Answer 2

-webkit-background-size background-position, .

Answer 3

, , px, -

background-size:100% 31px; background-repeat:no-repeat;

Answer 4

- ?

-webkit-gradient(linear, center bottom , #f00 2%, #d00 31px)

, .