diff --git a/src/lib/languages.ts b/src/lib/languages.ts
index b9238ed..30e7452 100644
--- a/src/lib/languages.ts
+++ b/src/lib/languages.ts
@@ -31,6 +31,7 @@ export const DEFAULT_LANGUAGES = [
   'sass',
   'scss',
   'stylus',
+  'sugarss',
   // js
   'javascript',
   'javascriptreact',
diff --git a/src/lsp/util/css.ts b/src/lsp/util/css.ts
index fc5f0a6..848d6bb 100644
--- a/src/lsp/util/css.ts
+++ b/src/lsp/util/css.ts
@@ -9,6 +9,7 @@ export const CSS_LANGUAGES = [
   'sass',
   'scss',
   'stylus',
+  'sugarss',
 ]
 
 function isCssDoc(state: State, doc: TextDocument): boolean {