diff --git a/css/css-images/gradient/gradient-eval-002-ref.html b/css/css-images/gradient/gradient-eval-002-ref.html
index 0a374154af6cc52..4db29f5ce9e9eab 100644
--- a/css/css-images/gradient/gradient-eval-002-ref.html
+++ b/css/css-images/gradient/gradient-eval-002-ref.html
@@ -7,6 +7,7 @@
    .test {
        width: 100px;
        height: 100px;
+       background: red;
        background: lab(60% 0 0);
    }
  </style>
diff --git a/css/css-images/gradient/gradient-eval-003-ref.html b/css/css-images/gradient/gradient-eval-003-ref.html
index 0a374154af6cc52..4db29f5ce9e9eab 100644
--- a/css/css-images/gradient/gradient-eval-003-ref.html
+++ b/css/css-images/gradient/gradient-eval-003-ref.html
@@ -7,6 +7,7 @@
    .test {
        width: 100px;
        height: 100px;
+       background: red;
        background: lab(60% 0 0);
    }
  </style>
diff --git a/css/css-images/gradient/gradient-eval-005-ref.html b/css/css-images/gradient/gradient-eval-005-ref.html
index cb2a4ed65c9abd9..b4a36ff6d0e43b3 100644
--- a/css/css-images/gradient/gradient-eval-005-ref.html
+++ b/css/css-images/gradient/gradient-eval-005-ref.html
@@ -7,6 +7,7 @@
    .test {
        width: 100px;
        height: 100px;
+       background: red;
        background: lch(60% 60 0);
    }
  </style>
diff --git a/css/css-images/gradient/gradient-eval-006-ref.html b/css/css-images/gradient/gradient-eval-006-ref.html
index c2a9500ad5cb19a..8ed6e683b278ee2 100644
--- a/css/css-images/gradient/gradient-eval-006-ref.html
+++ b/css/css-images/gradient/gradient-eval-006-ref.html
@@ -7,6 +7,7 @@
    .test {
        width: 100px;
        height: 100px;
+       background: red;
        background: lab(75% 0 0);
    }
  </style>
diff --git a/css/css-images/gradient/gradient-eval-007-ref.html b/css/css-images/gradient/gradient-eval-007-ref.html
index cb2a4ed65c9abd9..b4a36ff6d0e43b3 100644
--- a/css/css-images/gradient/gradient-eval-007-ref.html
+++ b/css/css-images/gradient/gradient-eval-007-ref.html
@@ -7,6 +7,7 @@
    .test {
        width: 100px;
        height: 100px;
+       background: red;
        background: lch(60% 60 0);
    }
  </style>
diff --git a/css/css-images/gradient/gradient-eval-008-ref.html b/css/css-images/gradient/gradient-eval-008-ref.html
index cb2a4ed65c9abd9..b4a36ff6d0e43b3 100644
--- a/css/css-images/gradient/gradient-eval-008-ref.html
+++ b/css/css-images/gradient/gradient-eval-008-ref.html
@@ -7,6 +7,7 @@
    .test {
        width: 100px;
        height: 100px;
+       background: red;
        background: lch(60% 60 0);
    }
  </style>
diff --git a/css/css-images/gradient/gradient-eval-009-ref.html b/css/css-images/gradient/gradient-eval-009-ref.html
index cb2a4ed65c9abd9..b4a36ff6d0e43b3 100644
--- a/css/css-images/gradient/gradient-eval-009-ref.html
+++ b/css/css-images/gradient/gradient-eval-009-ref.html
@@ -7,6 +7,7 @@
    .test {
        width: 100px;
        height: 100px;
+       background: red;
        background: lch(60% 60 0);
    }
  </style>