feat: ignore native CSS service not supporting yet

packages/language-service/src/lib/css-service.ts

@@ -143,6 +143,7 @@ export class CssService {
                         atRuleName === '@st-scope' ||
                         atRuleName === '@st-namespace' ||
                         atRuleName === '@st-import' ||
+                        atRuleName === '@container' ||
                         atRuleName === '@st-global-custom-property')
                 ) {
                     return false;
@@ -163,7 +164,7 @@ export class CssService {
                 } else if (diag.code === 'unknownProperties') {
                     const prop = diag.message.match(/'(.*)'/)![1];
 
-                    if (meta.getStVar(prop)) {
+                    if (meta.getStVar(prop) || prop === 'container' || prop === 'container-name') {
                         return false;
                     }
                 }

packages/language-service/test/lib/completions/contains.spec.ts

@@ -0,0 +1,25 @@
+import { expect } from 'chai';
+import { createDiagnostics } from '../../test-kit/diagnostics-setup';
+import deindent from 'deindent';
+
+describe('CSS contains', () => {
+    it('should ignore native css lsp diagnostics unknown container at-rule and declarations', () => {
+        // remove once css lsp supports is added or we implement the complete lsp ourselves
+        const filePath = '/style.st.css';
+
+        const diagnostics = createDiagnostics(
+            {
+                [filePath]: deindent`
+                    @container a (inline-size > 100px) {}
+                    .root {
+                        container-name: a;
+                        container: a / normal;
+                    }
+                `,
+            },
+            filePath
+        );
+
+        expect(diagnostics).to.eql([]);
+    });
+});