This web-based “Layer Styles” application has a very similar look to the one in Photoshop, allows us to play with the properties of an object but generates the output as CSS(3).
Just like Photoshop, it has ready-to-use styles and comes with the menus like:
drop shadow
inner shadow
background
border
border-radius
This HTML5 application is open sourced, mimics Photoshop perfectly and worth checking.