Enter the URL of any CSS file to view and modify its color spectrum
With this bookmarklet you can click a html element and get and edit an XPath/CSS Path expression to it.
Deadweight is RCov for CSS, kind of. Given a set of stylesheets and a set of URLs, it determines which selectors are actually used and reports which can be "safely" deleted.
Helium is a tool for discovering unused CSS across many pages on a web site. The tool is javascript-based and runs from the browser.
JsFiddle is a playground for web developers, a tool which may be used in many ways. One can use it as an online editor for snippets build from HTML, CSS and JavaScript. The code can then be shared with others, embedded on a blog, etc. Using this approach, JavaScript developers can very easily isolate bugs. We aim to support all actively developed frameworks - it helps with testing compatibility.