diff --git a/after/syntax/css/highlight-api-1.vim b/after/syntax/css/highlight-api-1.vim
new file mode 100644
index 0000000..d8a8b43
--- /dev/null
+++ b/after/syntax/css/highlight-api-1.vim
@@ -0,0 +1 @@
+syn region cssPseudoClassFn contained matchgroup=cssFunctionName start="\<highlight(" end=")" contains=cssStringQ,cssStringQQ
diff --git a/test/test.css b/test/test.css
index 8ac765c..1eb535e 100644
--- a/test/test.css
+++ b/test/test.css
@@ -417,6 +417,10 @@
 	display: auto;
 }
 
+.highlight-api-1::highlight(test) {
+	display: auto;
+}
+
 .html5,
 picture,
 rb,