Is it possible to have a child element behind his parent element with z-index

Question

I would like to know if it possible to have a child element behind his parent element with z-index.

I would like to use the parent div as transparent color layer on

Answer 1

While this wouldn't necessarily work in all browsers (especially older ones), the following has worked for me in the past:

#child {
  position: relative;
  z-index: -1;
  ...
}

I'm really only suggesting this as a last resort and would still prefer to use any technique other than this, although it might be ideal in your scenario.