HTML5 and CSS3 with WordPress

Ray Villalobos, who flew all the way out from Florida, opened the development track at WordCamp Developers with a talk about HTML5, CSS3, and WordPress integration. He posted his slides before the talk as well.

Ray is an author at and runs a course on iOS 4 and web applications. The WordCamp presentation grew out of this course. He works for Entravision Orlando full-time, which manages many Univision stations.

The talk covered core HTML5 and CSS3 concepts and how they can be implemented into your WordPress development.

Core concepts

Ray described HTML5 as a bit of a rebellion against XHTML 2.0. In other words, “XHTML 1.1 makes humans code like machines.” With its flexible parsing rules, support of existing code structure, and common tags HTML5 respects users, browsers, and lets people write code in a more fluid manner.

HTML5 brings support for semantic elements (header, footer, asides, etc.) along with rich media and new form elements.

The semantic tags in HTML5 were created by analyzing the tags people were already using in their markup. The goal was to make things easier and provide for more rapid prototyping.


Mobile browsers have great support for CSS3. Mobile app development allows for more universal support of both CSS3 and HTML5.

Ray warned to be careful when using gradients, custom fonts, transformations, and animations. Browser support for these elements can be dicey and relying on any of them for mission critical features isn’t a great idea.

One of the cool things with CSS3 is the media queries that allow for responsively designed sites. Ethan Marcotte also wrote a stellar article at A List Apart on media queries in May of last year.

Before adding new elements from HTML5 or CSS3 Ray cautions to look at your target platforms. Analyzing your site metrics will give you a better idea of what browsers your users are on. This helps you determine where to add enhancements and how vital it is to provide alternative versions.

To add support for semantic selectors in Internet Explorer and other browsers that don’t natively support them Ray suggested using html5shim or Modernizr.

Ray recommended Browser Labs from Adobe to test sites in multiple browsers side-by-side. It’s free right now but will eventually be a paid tool.

Using cache manifests and .htaccess rules you can easily set up offline storage of files on devices. These provide a great way to store images and other data for use in offline or airplane modes.