Added style sheet for petshop page from class2.

Attempted to build page in disciplined fashion by establishing document first ... before styling. Page is anything but bullet-proof though. Layout is sensitive [in particular,] to change in width of individual components. Ran into this issue when attempting to fine tune pixel alignment of page's components.

Isn't clear which is best ... work to define dimensions of page's components from outer containers in ... or define physical dimensions of lowest[inner] elements and allow containing components to inherit size [so-to-speak].

What doesn't work well is mixing the two techniques. It becomes difficult to predict how layout [behavior] is affected through minor change.

Anyway, there seems to be merit in reviewing coded css [in 2nd and 3rd passes] to look for opportunity to reduce/consolidate classes and identifiers.