How to create an overlay div to shadow the whole screen?

I am a new learner of html and jquery.

Please help me how I can create an overlay div which covers my whole screen, including the background image as well. I was able to create an overlay div but it does not covers my whole screen, instead it covers my container div an开发者_StackOverflow社区d if i increase the width it stretches to right side but left part remains uncovered.I put my overlay div in the outer most div but still on increasing the width it gives extra width to right side only and left part remains uncovered. . My wrapper div has a background image for the whole screen but my overlay div is not able to cover left part of my container div. Please help me.

thanks HP

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take a look at the blockUI plugin

http://jquery.malsup.com/block/

lots of different styles available! the page blocking example is what you need, it works with a div or a html string for the message while the overlay is shown.

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I got the answer. YOu can put margin:auto; Now, your browser will take care of it and it will occupy the whole screen.