From f69edda424f22d3cb8a59883f3469d8652cbe8f7 Mon Sep 17 00:00:00 2001
From: Ferit <frtcm11@gmail.com>
Date: Fri, 9 Oct 2026 23:50:54 +0300
Subject: [PATCH] Fix single-arg values inside nested at-rules

---
 index.js           |  2 +-
 test/index.test.js | 23 +++++++++++++++++++++++
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/index.js b/index.js
index adcbdc7..7255dc6 100644
--- a/index.js
+++ b/index.js
@@ -137,7 +137,7 @@ function unwrapSingleArguments(rules, singleArgumentsMap) {
         }
         rule.value = newValue
       }
-    } else if (rule.type === 'rule') {
+    } else if (rule.nodes) {
       unwrapSingleArguments(rule.nodes, singleArgumentsMap)
     }
   }
diff --git a/test/index.test.js b/test/index.test.js
index d927e39..9528b5d 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -497,6 +497,29 @@ test('handles single-arg inside rules', async () => {
   )
 })
 
+test('handles single-arg inside nested at-rules', async () => {
+  await run(
+    '@define-mixin fonts $x { @media screen { @supports (display: grid) ' +
+      '{ .a { font-family: $x } } } } @mixin fonts single-arg(Arial, sans-serif);',
+    '@media screen { @supports (display: grid) ' +
+      '{ .a { font-family: Arial, sans-serif } } }'
+  )
+})
+
+test('handles single-arg in object mixin at-rules', async () => {
+  await run(
+    '@mixin fonts single-arg(Arial, sans-serif);',
+    '@media screen {\n    font-family: Arial, sans-serif\n}',
+    {
+      mixins: {
+        fonts(rule, font) {
+          return { '@media screen': { fontFamily: font } }
+        }
+      }
+    }
+  )
+})
+
 test('passes single-arg to the nested mixin', async () => {
   await run(
     '@define-mixin a $p { a: $p; } ' +