fix: feedback

Author: Netail

css/at-rules.json

@@ -121,15 +121,14 @@
     "mdn_url": "https://developer.mozilla.org/docs/Web/CSS/@counter-style"
   },
   "@container": {
-    "syntax": "@container <container-condition># {\n  <block-contents>\n}",
+    "syntax": "@container <container-condition># {\n  <group-rule-body>\n}",
     "interfaces": [
       "CSSGroupingRule",
       "CSSConditionRule",
       "CSSContainerRule"
     ],
     "groups": [
-      "CSS Conditional Rules",
-      "CSS Containment"
+      "CSS Conditional Rules"
     ],
     "status": "standard",
     "mdn_url": "https://developer.mozilla.org/docs/Web/CSS/@container"