diff --git a/after/syntax/css/css-timing-1.vim b/after/syntax/css/css-timing-1.vim
new file mode 100644
index 0000000..e21f31b
--- /dev/null
+++ b/after/syntax/css/css-timing-1.vim
@@ -0,0 +1 @@
+syn region cssFunction contained matchgroup=cssFunctionName start="\<frames\s*(" end=")" oneline keepend
diff --git a/after/syntax/html.vim b/after/syntax/html.vim
index 581829c..85e97a7 100644
--- a/after/syntax/html.vim
+++ b/after/syntax/html.vim
@@ -38,6 +38,7 @@ syn include @htmlCss syntax/css/css-syntax-3.vim
 syn include @htmlCss syntax/css/css-text-3.vim
 syn include @htmlCss syntax/css/css-text-4.vim
 syn include @htmlCss syntax/css/css-text-decor-3.vim
+syn include @htmlCss syntax/css/css-timing-1.vim
 syn include @htmlCss syntax/css/css-transforms-1.vim
 syn include @htmlCss syntax/css/css-typed-om-1.vim
 syn include @htmlCss syntax/css/css-ui-3.vim
diff --git a/test/test.css b/test/test.css
index 6639056..720eb20 100644
--- a/test/test.css
+++ b/test/test.css
@@ -672,6 +672,10 @@
   display: over;
 }
 
+.timing-1 {
+  display: frames(2);
+}
+
 .transforms-1 {
   backface-visibility: flat;
   perspective: preserve-3d;
diff --git a/test/test.html b/test/test.html
index 5c30bf0..583beec 100644
--- a/test/test.html
+++ b/test/test.html
@@ -741,6 +741,11 @@
 }
 </style>
 <style>
+.timing-1 {
+  display: frames(2);
+}
+</style>
+<style>
 .transforms-1 {
   backface-visibility: flat;
   perspective: preserve-3d;