Learn how to keep your HTML and CSS code up to digital publishing standards with validator tools, semantic markup, naming conventions, code optimization techniques, and testing tools.

Dabblet, created by Lea Verou, is an “interactive playground” for trying out snippets of CSS and HTML code.It uses -prefix-free, so that you won’t have to add any prefixes in your CSS code ...

How to Add an Image to a CSS File. Web pages normally add images using the inline HTML "img" tag. CSS coding usually doesn't set an image's source because CSS ... Add the following code to insert ...