If you can’t do it Keynote, it is unlikely you could achieve it in HTML/CSS.
Not stated in the linked article but worth noting: Photoshop CS6 is going to cost me somewhere in the $900 range to upgrade from Design Premium CS4 (unless Adobe finally – pretty please! – lets you upgrade single applications instead of the entire suite). Keynote costs $20.
Who I Am (short version)
I’m a web developer for Validic, and I live in Carrboro, NC, USA.