---- CSS example: 100% height, footer stuck on bottom
swa66 - 12:50 pm on Nov 12, 2009 (gmt 0)
why use .header etc rather than #header
elements in your html with class="header" can be selected in CSS with ".header" the element in your html with id="header" can be selected in CSS with "#header"
So the question might be when to use a class or an id. An id is only allowed once in a html document, a class can occur multiple times. In this case an id would have done just fine, it can even be argued to be better.
I didn't stop to think about it (the goal was different), if I did I might actually have gone for an id in hindsight.