Include files can also be handy for repeating standardized content such as payment policies, privacy policies, or other “boilerplate” business or legal language that is repeated in identical form in many places throughout a large site. Always look for opportunities to pull repeating content out of the page files and into an include file. If you ever have to change the boilerplate language, you’ll be glad you have to change just one file to update every occurrence of the text throughout the site.
Using the cascade in CSS
Many users of Cascading Style Sheets know how to change the look of standard html components but don’t pay much attention to the powerful cascade features of css. css is an extendable system, in which a related set of css instructions spread across multiple css files can cascade from very general style and layout instructions shared by all of your pages to extremely specific styles that only a handful of pages in your site may share. The css cascade has two major elements:
1. CSS cascade hierarchy
css has multiple hierarchical levels that cascade in importance and priority, from general css code shared by all pages, to code that is contained in a particular page file, to code that is embedded in specific html tags. General page code overrides shared site code, and css code embedded in html tags overrides general page code. This hierarchical cascade of css priorities allows you to set very general styles for your whole site while also permitting you to override the styles where needed with specific section or page styles (fig. 5.5).