cdoublev
diff --git a/‎lib/parse/arbitrary.js‎
Lines changed: 3 additions & 0 deletions b/‎lib/parse/arbitrary.js‎
Lines changed: 3 additions & 0 deletions
diff --git a/‎lib/values/definitions.js‎
Lines changed: 1 addition & 1 deletion b/‎lib/values/definitions.js‎
Lines changed: 1 addition & 1 deletion
diff --git a/‎scripts/extract.js‎
Lines changed: 0 additions & 2 deletions b/‎scripts/extract.js‎
Lines changed: 0 additions & 2 deletions
diff --git a/‎test/style.js‎
Lines changed: 1 addition & 1 deletion b/‎test/style.js‎
Lines changed: 1 addition & 1 deletion
@@ -137,6 +137,9 @@ function matchFreeFormValue(node, match) {
             }
             return error(node)
         }
+        if (isProducedBy(node, '<if-args-branch>')) {
+            return match(node, [',', '{', ':'])
+        }
         return match(node, [',', '{'])
     }
     return match(node)
 
@@ -245,7 +245,7 @@ export default {
     '<ident-arg>': '<string> | <integer> | <ident>',
     '<ident>': '<ident-token>',
     '<if()>': 'if([<if-branch> ;]* <if-branch> ;?)',
-    '<if-args-branch>': '<declaration-value> [: <declaration-value>?]?',
+    '<if-args-branch>': '<declaration-value> : <declaration-value>?',
     '<if-args>': 'if([<if-args-branch> ;]* <if-args-branch> ;?)',
     '<if-branch>': '<if-condition> : <declaration-value>?',
     '<if-condition>': '<boolean-expr[<if-test> ]> | else',
 
@@ -201,8 +201,6 @@ const replaced = {
         '<feature-index>': '<integer>',
         // https://github.com/w3c/csswg-drafts/issues/13010
         '<event-trigger-event>': 'activate | click | touch | dblclick | keypress(<string>)',
-        // https://github.com/w3c/csswg-drafts/issues/12487
-        '<if-args-branch>': '<declaration-value> [: <declaration-value>?]?',
         // https://github.com/w3c/fxtf-drafts/issues/532
         '<mask-reference>': 'none | <image>',
         // TODO: fix `value` of `<pseudo-page>`
 
@@ -656,7 +656,7 @@ describe('arbitrary substitution', () => {
             ['--custom(--custom(!))'],
             ['attr(name, attr())'],
             ['env(name, env())'],
-            ['if(if())', 'if(if())'],
+            ['if(if():)'],
             ['inherit(--custom, inherit())'],
             ['random-item(--key, random-item())'],
             ['var(--custom, var())'],
@@ -137,6 +137,9 @@ function matchFreeFormValue(node, match) {
137	137	}
138	138	return error(node)
139	139	}
	140	+ if (isProducedBy(node, '<if-args-branch>')) {
	141	+ return match(node, [',', '{', ':'])
	142	+ }
140	143	return match(node, [',', '{'])
141	144	}
142	145	return match(node)