HTML Guide for background-image
A CSS definition for background-image could not be understood by the parser. Check its definition to ensure that it’s well formed and that it contains an appropriate value.
background-image attribute values must use valid CSS syntax.
The background-image property in CSS expects the value to be a valid image reference, such as none, url("image.png"), gradients, or inherit.
Correct CSS Syntax:
background-image: url("background.jpg");
Correct usage in HTML (inline style):
<div style="background-image: url('background.jpg');">
Content here
</div>
Incorrect usage (missing url() or filename only):
<div style="background-image: background.jpg;">
Content here
</div>
Correct usage in a <style> block:
<!DOCTYPE html>
<html lang="en">
<head>
<title>Background Image Example</title>
<style>
.banner {
background-image: url("banner.png");
}
</style>
</head>
<body>
<div class="banner">Welcome</div>
</body>
</html>
Always wrap the image path with the url() function and use quotes for paths containing special characters.