How to Change a Background Dynamically in a Website. Using CSS and JavaScript, you can dynamically change the background on your website.

How to learn HTML, CSS and web design on your Mac: Create a simple page Building web pages really couldn’t be easier. Web pages are (mostly) set up using HTML (Hyper Text Markup Language).

One way to add a background photo to any custom Tumblr theme is to embed a simple CSS tag at the right location in the theme's HTML code.

The ! important flag ensures that your CSS styles override those of the page itself. Effectively, what this does is to add these lines to the header of your HTML page: background-color: #ffffff ...

jsFiddle lets developers play with the three core elements of Web development. Check out this powerful application for rapid prototyping and testing.