CSS for Autosizing Image to Browser window help!!!

[jwtelectric]

i need the css for making and image fit to window on open
and then the mouse cursor turn to magniying glass on hover
and resize image to full size on click
then resize back to fit window on click
thanks

[bluewalrus]

Dont' double post.... and if you do don't give less detail.

[jwtelectric]

wan't sure if this was css or html
sorry