The @charset CSS rule specifies the character encoding used in the style sheet. This syntax is useful when using non-ASCII characters in some CSS properties, like content. Although the first character in @charset is the @ symbol, it is not an at-rule. It is a specific byte sequence that can only be placed at the very beginning of a stylesheet. No other characters, except the Unicode byte-order mark, are allowed before it. It also does not follow normal CSS syntax rules such as use of quotes or whitespace....following order (and stop as soon as one yields a result): The value of...double-quoted, following exactly one space character (U+0020), and...