Relative text area size?

[Cele]

If I have a text area defined to be certain px from left, certain px from top... And certain height, is it possible to make it so the height is always x amount of px from the screen bottom? So it would display in different sizes on different devices.

Code

<div id="textarea" style="position:absolute; top:120px; left:160px; width:750px; height:700px;">

How to replace height 700px with, height is always 80px from the screen bottom?

[doubleincision]

i rarely use calc so i may be wrong, but i think it can achieve what you're looking for?

[Nullcasting]

   you could try doing percentages instead?

like this:
sudocss {
margin-botton: 35%
}
should theoretically make it so sudocss is 35% off the bottom of the screen. i think.