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CSS syntax - CSS | MDN
Note:
The module explicitly states that @charset@charset usage is at the very beginning of a stylesheet, where it is interpreted as a special byte sequence stripped before processing the content.
Introduction to CSS syntax: declarations, rulesets, and statements
Explains the overall CSS syntax and how declarations, declaration blocks, rulesets, and statements form the style rules.
Value definition syntax
Explains the formal grammar for defining valid values for CSS properties and functions, along with semantic constraints. A guide for understanding CSS component value types, combinators, and multipliers.
CSS error handling
Overview of how browsers handle invalid CSS.
Learn CSS first steps: CSS syntax
Introductory guide to CSS, including an introduction to CSS syntax.
