To select an element tag or attribute defined in a specific namespace, you declare a namespace prefix with an @namespace rule, then use it in your selector. The namespace is separated from the tag name with a | (vertical bar or pipe) character; if there is no tag name in the selector, use a universal * selector:
```css @namespace svg "http://www.w3.org/2000/svg";
a { / These rules would apply to any a elements. /
text-decoration: underline;
color: purple;
}
svg|a { / These rules would apply to SVG a elements,
but not HTML links. /
stroke: purple;
}
svg| { / These rules apply to all SVG-namespaced elements,
but not HTML elements. */
mix-blend-mode: multiply;
}
```