How to add dialog box on webpage with Chrome Extension?

Does a开发者_开发知识库nyone know how to add a dialog box similar to the one used by Google's Voice extension (it's the one in the blue activated by clicking on the phone number)?

Thanks, Joe Chin

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Chrome doesn't come with any GUI API. Everything you see is made in plain javascript and css. You would need to either find some js library that helps with creating dialogs, or style them yourself (that's what that Google Voice extension looks like is doing).