Greepit previously shared an HTML5-CSS3 project template that contains the basic structure for starting a new HTML5-CSS3 project.
Mobile Boilerplate is your trusted template made custom for creating rich and performant mobile web applications. You get cross-browser consistency among A-grade smartphones, and fallback support for legacy Blackberry, Symbian, and IE Mobile.
Mobile Boilerplate is not a framework, but works well with projects like jQuery Mobile, Sencha Touch, Phonegap and Appcelerator. You get an offline caching setup for free, fast button clicks, a media query polyfill, and many common mobile WebKit optimizations waiting for you.