\ must be followed by a newline

For each pair of consecutive token, look in the tables below. Rows and columns are first and second tokens, respectively. If a combination is marked with an ✓, a comment must be inserted between such two tokens during serialization.

identfunctionurlbad-url-numberpercentagedimensionunicode-rangeCDC(
ident
at-keyword
hash
dimension
#
-
number
@
unicode-range
.
+
=|*
$
*
^
~
|
/