diff --git a/js/csslint/parserlib.js b/js/csslint/parserlib.js
index ec17b3d1..c244c2d3 100644
--- a/js/csslint/parserlib.js
+++ b/js/csslint/parserlib.js
@@ -2408,9 +2408,6 @@ self.parserlib = (() => {
       }
       return;
     }
-    if (hasVarParts(value)) {
-      return;
-    }
     const prop = lower(name);
     let known = validationCache.get(prop);
     if (known && known.has(value.text)) {
@@ -2423,6 +2420,9 @@ self.parserlib = (() => {
     if (!spec) {
       throw new ValidationError(`Unknown property '${name}'.`, value);
     }
+    if (hasVarParts(value)) {
+      return;
+    }
     // Property-specific validation.
     const expr = new PropertyValueIterator(value);
     const m = Matcher.parse(spec);