CSS Rules Exclusively for Firefox

While conditional comments effectively target Internet Explorer with browser-specific CSS, the challenge remains in targeting Firefox specifically. To address this, seek a solution that avoids browser-sniffing JavaScript and leverages browser capabilities similar to conditional comments.

Exclusive Firefox Targeting

A solution that meets these criteria is as follows:

@-moz-document url-prefix() {
  h1 {
    color: red;
  }
}

This rule targets elements with the url-prefix() function, which is unique to Firefox. It ensures that the CSS rules are applied only in Firefox and not in any other browser, including Internet Explorer, WebKit, or Opera.

To use this rule, simply add it to your CSS file. When the browser renders it in HTML, the

element will appear in red only in Firefox.

This solution relies solely on browser capabilities, providing a clean and highly specific way to target Firefox without any JavaScript trickery.