Comment by mushyhammer

Contrary to popular belief, HTML and CSS are unrelated.

If any CSS property was also an HTML attribute, any addition to either spec would have to make sure it wouldn’t conflict. One example is the `content` HTML attribute and CSS property. They serve different purposes and have a completely different syntax.

    <meta name="description" content="Cool stuff”>

and

    .css::before {
        content: url(image.bmp)
    }