diff --git a/README.md b/README.md
index e5a3255b..fd25099f 100644
--- a/README.md
+++ b/README.md
@@ -1014,29 +1014,11 @@ roborazzi {
 }
 ```
 
-<details>
-<summary>build.gradle version</summary>
-<br>
-
-```groovy
-roborazzi {
-    generateComposePreviewRobolectricTests.enable.set(true)
-    // The package names to scan for Composable Previews.
-    generateComposePreviewRobolectricTests.packages.set(["com.example"])
-    // robolectricConfig will be passed to Robolectric's @Config annotation in the generated test class.
-    // See https://robolectric.org/configuring/ for more information.
-    generateComposePreviewRobolectricTests.robolectricConfig.set([
-        "sdk": "[32]",
-        "qualifiers": "RobolectricDeviceQualifiers.Pixel5",
-    ])
-    // If true, the private previews will be included in the test.
-    generateComposePreviewRobolectricTests.includePrivatePreviews.set(true)
-    // The fully qualified class name of the custom test class that implements [com.github.takahirom.roborazzi.ComposePreviewTester].
-    generateComposePreviewRobolectricTests.testerQualifiedClassName.set("com.example.MyCustomComposePreviewTester")
-}
-```
-
-</details>
+> **Note**  
+> If you are using build.gradle instead of build.gradle.kts, you need to use the set method for each assignment, like
+> ```kotlin
+> generateComposePreviewRobolectricTests.packages.set(["com.example"])
+> ```
 
 ## Manually adding Compose Preview screenshot tests
 
diff --git a/docs/topics/preview_support.md b/docs/topics/preview_support.md
index 8bf6a879..42ec43c2 100644
--- a/docs/topics/preview_support.md
+++ b/docs/topics/preview_support.md
@@ -45,30 +45,11 @@ roborazzi {
 }
 ```
 
-<details>
-<summary>build.gradle version</summary>
-<br>
-
-```groovy
-roborazzi {
-    generateComposePreviewRobolectricTests.enable.set(true)
-    // The package names to scan for Composable Previews.
-    generateComposePreviewRobolectricTests.packages.set(["com.example"])
-    // robolectricConfig will be passed to Robolectric's @Config annotation in the generated test class.
-    // See https://robolectric.org/configuring/ for more information.
-    generateComposePreviewRobolectricTests.robolectricConfig.set([
-        "sdk": "[32]",
-        "qualifiers": "RobolectricDeviceQualifiers.Pixel5",
-    ])
-    // If true, the private previews will be included in the test.
-    generateComposePreviewRobolectricTests.includePrivatePreviews.set(true)
-    // The fully qualified class name of the custom test class that implements [com.github.takahirom.roborazzi.ComposePreviewTester].
-    generateComposePreviewRobolectricTests.testerQualifiedClassName.set("com.example.MyCustomComposePreviewTester")
-}
-```
-
-</details>
-
+> **Note**  
+> If you are using build.gradle instead of build.gradle.kts, you need to use the set method for each assignment, like
+> ```kotlin
+> generateComposePreviewRobolectricTests.packages.set(["com.example"])
+> ```
 
 ## Manually adding Compose Preview screenshot tests