How to highlight just a PART of Web page displayed in WebBrowser control??

I need to highlight (programmatically) the top part of the Web page displayed in WebBrowser control. It can be 50% or 25% or even 10% of the full web page page, depending on user choice.

Any suggestions of how to do this programmatically?

Thanks!

You can dim the rest of the page by injecting a transparent DIV (styled with absolute position) over the bottom of the page.

cheers,
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Thank you for suggestion!:)