i have div area which is devided in to 4 equal parts, like the one atached.
now i need another div to be placed at the bottom area as an overlay to the above div. Imagine it like a text scroll area on the bottom side of the TV and the TV screen is constructed by 4 divs.
I am able to create the 5 divs. now the issue is that the 5th div(scroll area) is not going above the bottom edge of the 2 lower divs (3 and 4). I also had put z-index also but failed
can anybody share a sample for styling this.

You can solve it this way:
HTML:
CSS:
Please note that I have used hard coded example values. The actual values depends on which context the markup is in.