This pixel grid, essentially made out of one class called .pixel-grid, wich i put into a div frame for its centered prosition to show some fun things you can do with pure HTML5/CSS3.
The width and height of the frame determines the amount of pixels on screen: If every pixel dot is 10x10px, and the frame is width: 120x160px, the visible area is 12x16 pixels.
check out the example at http://codepen.io/FRickReich/full/nhzDa/!