According to the W3C specifications:
A string cannot directly contain a newline. To include a newline in a string, use an escape representing the line feed character in ISO-10646
(U+000A), such as "\A" or "\00000a".
[…]
It is possible to break strings over several lines, for aesthetic or other reasons, but in such a case the newline itself has to be escaped with
a backslash (\).
Noncompliant code example
a {
content: "first
second";
}
Compliant solution
a {
content: "first\Asecond";
}
