Firefox Add-ons
https://addons.mozilla.org/en-US/firefox/addon/60
This has been one of my most useful tools I have when it comes to CSS and tweaking my websites. This add on basically has the ability to strip out the CSS, Disable the CSS, Edit the CSS, are you starting to see a theme here. It’s a great tool. Just download it and see for yourself.

• Ctrl + Shift + Y = View Style Information