HTML and CSS Reference
In the previous chapters, the focus was on understanding the build-
ing blocks and elements that make up the language of Cascading Style
Sheets. In Chapter 7, we used those elements to create some commonly
used layout and grid structures.
But often, the task of building a web site does not start with rebuilding
all elements from scratch; instead, it often starts with reusing elements
by drawing from a library of code you've previously written or open
source code for libraries or elements that you can use.