Styling with CSS (Cascading Style Sheets)
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Common Attributes
class-
Assigns a class name or set of class names to an element. You may assign the same class name or names to any number of elements, however, multiple class names must be separated by whitespace characters. It serves a key role as a style sheet selector, for when an author assigns style information to a set of elements.
id- Assigns a unique ID
lang- Indicates that the page is written in a given language. Values are two letters:
en,es,de(for German),fretc.