diff --git a/src/extension.ts b/src/extension.ts
index 1772b46..e6bdc8c 100644
--- a/src/extension.ts
+++ b/src/extension.ts
@@ -186,7 +186,7 @@ export async function activate(context: ExtensionContext): Promise<void> {
     });
 
     // CSS based extensions
-    ["css", "sass", "scss"].forEach((extension) => {
+    ["css", "sass", "scss", "postcss"].forEach((extension) => {
         // Support for Tailwind CSS
         context.subscriptions.push(provideCompletionItemsGenerator(extension, /@apply ([\.\w- ]*$)/, "."));
     });