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The specified CSS mask has incorrect or unrecognized values. Ensure that the mask property is used correctly according to the CSS specifications.
The mask CSS shorthand property hides an element (partially or fully) by masking or clipping the image at specific points.
For example, the mask-image CSS property sets the image that is used as mask layer for an element. By default this means the alpha channel of the mask image will be multiplied with the alpha channel of the element, as in thie example:
<!DOCTYPE html>
<html lang="en">
<head>
<title>Test</title>
<style>
.masked {
width: 100px;
height: 100px;
background-color: #8cffb0;
-webkit-mask-image: url(sun.svg);
mask-image: url(sun.svg);
}
</style>
</head>
<body>
<div class="masked"></div>
</body>
</html>Learn more:
Related W3C validator issues
The @tailwind at-rule defined by the Tailwind CSS framework isn’t officialy supported by the W3C Validator.
Tailwind directives are custom Tailwind-specific at-rules you can use in your CSS that offer special functionality for Tailwind CSS projects.
Although they’re valid directives for Tailwind, they’re not valid from the W3C Validator perspective. You can consider muting this issue in your Rocket Validator Pro reports.