diff --git a/after/syntax/css/color-hdr-1.vim b/after/syntax/css/color-hdr-1.vim
index a5e67fe..f495b24 100644
--- a/after/syntax/css/color-hdr-1.vim
+++ b/after/syntax/css/color-hdr-1.vim
@@ -1,3 +1,4 @@
 syn keyword cssFontProp contained dynamic-range-limit
 syn keyword cssFontAttr contained standard constrained-high
 syn region cssFunction contained matchgroup=cssFunctionName start="\<dynamic-range-limit-mix\s*(" end=")" oneline keepend
+syn region cssFunction contained matchgroup=cssFunctionName start="\<hdr-color\s*(" end=")" keepend
diff --git a/test/test.css b/test/test.css
index 9e3228f..6ed7811 100644
--- a/test/test.css
+++ b/test/test.css
@@ -245,6 +245,10 @@
   display: standard;
   display: constrained-high;
   display: dynamic-range-limit-mix(standard 10%, constrained-high 40%, high 50%);
+  display: hdr-color(
+    color(rec2100-linear 0.9 1.0 0.8) 0,
+    color(rec2100-linear 1.8 2.0 1.5) 2
+  );
 }
 
 .compositing-1 {