Galen Framework : Automated testing of look and feel for your responsive websites.
Layout testing seemed always a complex task. Galen Framework offers a simple solution...
* { CSS:resetr } : To help you find the perfect CSS-reset styles, CSSresetr lets you try all the best CSS Resets on a variety of web pages – even your own.
Screenfly : Test Your Website at Different Screen Resolutions
Diagnostic.css : Diagnostic.css is a stylesheet which allows the user to test for common errors in a page's markup.
Also : https://github.com/karlgroves/diagnostic.css
enquire.js : A lightweight, pure JavaScript library for responding to CSS media queries.
Breaking CSS is easy. Checking every responsive page element is hard. That’s why there's BackstopJS.
