z-index keyword proposal

A short extension proposal for z-index: keywords for above all other 
stacked boxes, and below all other stacked boxes.  Use case is if you 
don't know in advance how many boxes you'll be stacking, but you know 
you want a certian box to be above all the others.  Rather than picking 
a very large z-index, just use a keyword such as top or above.  If more 
than one box has the same top or bottom keyword, normal rules apply as 
if they had the same integer value.

'z-index'
     Value:   auto | <integer> | top | bottom | inherit
     Initial:   auto
     Applies to:   positioned elements
     Inherited:   no
     Percentages:   N/A
     Media:   visual

For a positioned box, the 'z-index' property specifies:

    1. The stack level of the box in the current stacking context.
    2. Whether the box establishes a local stacking context.

Values have the following meanings:

<integer>
     This integer is the stack level of the generated box in the current 
stacking context. The box also establishes a local stacking context in 
which its stack level is '0'.

top
     The stack level of the generated box is greater than all other 
boxes with a defined integer value.

bottom
     The stack level of the generated box is less than all other boxes 
with a defined integer value.

auto
     The stack level of the generated box in the current stacking 
context is the same as its parent's box. The box does not establish a 
new local stacking context.

--
Dylan Schiemann
http://www.sitepen.com/
http://www.dylanschiemann.com/

Received on Friday, 13 December 2002 15:26:14 UTC