See the demo here
In order to use a device, visit the index.html file and pick which one you want, copying the 'device' class and all it's children. The CSS is set up so that class has to be a wrapped in an element of ID which corresponds to the device you're picking.
Similarly if you want a different colour or to toggle it to be landscape, just add the respective colour class to the wrapping element, eg. 'red' or 'gold' or 'white' and the landscape class 'landscape':
#iphone5s (black by default) - .landscape, .white + .gold
#iphone5c (black by default, could be an iPhone 5) - .landscape, .white + .red + .yellow + .green
#ipad (black by default) - .landscape, .silver
#iphone4s (black by default) - .landscape, .silver
#nexus5 - .landscape
#lumia920 (yellow by default) - .landscape, .black + .white + .yellow + .red + .blue
#s5 (white by default) - .landscape, .black
#htc-one - .landscape
#iphone5s.landscape.gold
.device
.inner
.sleep
.volume
.camera
.top-bar
.sensor
.speaker
.screen
Screen content goes here
.bottom-bar
.home
Will give you a gold landscape iPhone 5S! The CSS is quite messy (taken directly from the Prototype view of Marvel), so use it, tweak it and improve however you want! Also sign up for Marvel if you haven't already because it's great