Specify single or double quotes around strings.
a[id="foo"] { content: "x"; }
/** ↑ ↑ ↑ ↑
* These quotes and these quotes */Quotes within comments are ignored.
/* "This is fine" */
/* 'And this is also fine' */Single quotes in a charset @-rule are ignored as using single quotes in this context is incorrect according the CSS specification.
@charset "utf-8"
/* fine regardless of configuration */string: "single"|"double"
Strings must always be wrapped with single quotes.
The following patterns are considered violations:
a { content: "x"; }a[id="foo"] {}The following patterns are not considered violations:
a { content: 'x'; }a[id='foo'] {}Strings must always be wrapped with double quotes.
The following patterns are considered violations:
a { content: 'x'; }a[id='foo'] {}The following patterns are not considered violations:
a { content: "x"; }a[id="foo"] {}