What is the best way to design a website?

What is the best way to style/design a website so that its parts could easily be ported into another website?

• The XHTML mark-up would be quite easy to port. But how about the CSS? For instance, one block-element can have its specific properties/style but then it can also be inheriting some of its properties somewhere. If I were to make another site and need to use the same style for one of its block-elements, then I have to trace back the entire hierarchy (from great-grandparent to child). But then I cannot automatically just copy and paste the entire hierarchy for the new site cause then, other elements will get affected globally. Also, let's say that at the onset, we aren't sure which parts we are going to re-use for another site. Is there an efficient way of doing this?

• Answer:

  I would just try and standardize your markup. Use semantic markup instead of coding stuff by appearance (i.e. not <div class="red-notification"> but <div class="warning notification urgent">). Use multiple classes to style different elements the same way (i.e. .notification can always have a specific font in CSS, whether it's a button or a div or a text input field or a paragraph).