CSS Demo: attr()

<blockquote cite="https://mozilla.org/en-US/about/">Mozilla makes browsers, apps, code and tools that put people before profit.</blockquote>

<blockquote cite="https://web.dev/about/">Google believes in an open, accessible, private, and secure web.</blockquote>

<blockquote cite="https://mozilla.org/en-US/about/">Mozilla makes browsers, apps, code and tools that put people before profit.</blockquote>

<blockquote cite="https://web.dev/about/">Google believes in an open, accessible, private, and secure web.</blockquote>

blockquote {
    margin: 1em 0;
}

blockquote::after {
    display: block;
    content: ' (source: ' attr(cite) ') ';
    color: hotpink;
}

blockquote {

margin: 1em 0;

}

blockquote::after {

display: block;

content: ' (source: ' attr(cite) ') ';

color: hotpink;

}

CSS Demo: attr()

Output

Console Output