resolve media query bug involving multiple identifiers

src/parse/media.rs

@@ -155,6 +155,7 @@ impl<'a> Parser<'a> {
                 }
             }
 
+            buf.push(' ');
             let ident = self.parse_identifier()?;
 
             self.whitespace();

tests/media.rs

@@ -31,3 +31,12 @@ test!(
     }",
     "@media screen {\n  a b {\n    color: red;\n  }\n  a c {\n    color: green;\n  }\n}\n"
 );
+test!(
+    multiple_identifiers_in_query,
+    "@media not screen {
+        a {
+            color: red;
+        }
+    }",
+    "@media not screen {\n  a {\n    color: red;\n  }\n}\n"
+);