Cascading Style Sheets: "Defining Style Rules"
This short chapter spells out the syntax for style rules in CSS that you may have already deduced from the examples in the "Syntax" chapter of Cascading Style Sheets you read in sub-subunit 1.4.3: The Essential Anatomy of an External CSS File.
Based on what you have just read, take a look at your "mystylesheets.css" file and see if you can identify the different parts of each style and guess their function. Consider experimenting with these styles to see if you can change how your "index.htm" file appears in the Web browser - but remember to keep back-up copies of your files!
Click https://en.wikibooks.org/wiki/Cascading_Style_Sheets/Defining_Style_Rules link to open resource.