diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index a5329b1..483a12f 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -168,12 +168,6 @@ unit-test-oni-conf:
     - package
   script: make unit-test-oni-conf TEST_ARCHIVE=$(realpath bin/)
 
-unit-test-oni-css:
-  stage: unit-test
-  dependencies:
-    - package
-  script: make unit-test-oni-css TEST_ARCHIVE=$(realpath bin/)
-
 unit-test-oni-elisp:
   stage: unit-test
   dependencies:
@@ -239,6 +233,13 @@ integration-test-oni-csharp:
     - package
   script: make integration-test-oni-csharp TEST_ARCHIVE=$(realpath bin/)
 
+integration-test-oni-css:
+  stage: integration-test
+  image: registry.gitlab.com/ryuslash/emacs-config
+  dependencies:
+    - package
+  script: make integration-test-oni-css TEST_ARCHIVE=$(realpath bin/)
+
 integration-test-oni-bookmark:
   stage: integration-test
   image: registry.gitlab.com/ryuslash/emacs-config
diff --git a/test/integration/oni-css.bats b/test/integration/oni-css.bats
new file mode 100644
index 0000000..66c625c
--- /dev/null
+++ b/test/integration/oni-css.bats
@@ -0,0 +1,11 @@
+#!/usr/bin/env bats
+
+@test "Opening a .css file loads oni-css" {
+    run emacs -batch -l package -f package-initialize \
+        -visit test.css \
+        -eval "(prin1 (featurep 'oni-css))"
+
+    echo "$output"
+
+    [[ "$output" == *"t" ]]
+}
diff --git a/test/oni-css-test.el b/test/oni-css-test.el
deleted file mode 100644
index 3ee55e3..0000000
--- a/test/oni-css-test.el
+++ /dev/null
@@ -1,36 +0,0 @@
-;;; oni-css-test.el --- Tests for oni-css            -*- lexical-binding: t; -*-
-
-;; Copyright (C) 2019  Tom Willemse
-
-;; Author: Tom Willemse <tom@ryuslash.org>
-;; Keywords: local
-
-;; This program is free software; you can redistribute it and/or modify
-;; it under the terms of the GNU General Public License as published by
-;; the Free Software Foundation, either version 3 of the License, or
-;; (at your option) any later version.
-
-;; This program is distributed in the hope that it will be useful,
-;; but WITHOUT ANY WARRANTY; without even the implied warranty of
-;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-;; GNU General Public License for more details.
-
-;; You should have received a copy of the GNU General Public License
-;; along with this program.  If not, see <https://www.gnu.org/licenses/>.
-
-;;; Commentary:
-
-;;
-
-;;; Code:
-
-(ert-deftest oni-css-test-autoloads ()
-  "Test that ‘oni-css’ gets loaded automatically."
-  (should (not (featurep 'oni-css)))
-  (require 'css-mode)
-  (should (featurep 'oni-css))
-  (unload-feature 'oni-css t)
-  (unload-feature 'css-mode t))
-
-(provide 'oni-css-test)
-;;; oni-css-test.el ends here