About This HTML Issue
Use the correct direction keyword syntax in CSS gradients: replace top with to top.
In CSS Images Level 4, the first argument of linear-gradient() should either be an angle (e.g., 180deg) or a direction using the to keyword (e.g., to top, to right). Older syntax like linear-gradient(top, ...) is no longer valid and triggers validator errors. Valid forms include: linear-gradient(to top, #fff, #000), linear-gradient(180deg, #fff, #000), or simply omit the direction to default to to bottom. Keep gradients in your CSS, not HTML attributes. The style attribute or a stylesheet can set the background or background-image with a valid gradient function.
HTML Examples
Example showing the issue
<!DOCTYPE html>
<html lang="en">
<head>
<title>Gradient Issue</title>
<style>
.box {
width: 200px;
height: 100px;
background: linear-gradient(top, #ffffff, #000000); /* invalid */
}
</style>
</head>
<body>
<div class="box"></div>
</body>
</html>Fixed example (valid syntax)
<!DOCTYPE html>
<html lang="en">
<head>
<title>Gradient Fixed</title>
<style>
.box {
width: 200px;
height: 100px;
/* Option A: direction keyword */
background: linear-gradient(to top, #ffffff, #000000);
/* Option B: angle (equivalent) */
/* background: linear-gradient(0deg, #ffffff, #000000); */
}
</style>
</head>
<body>
<div class="box"></div>
</body>
</html>Learn more:
Last reviewed: August 12, 2025
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