title: Extract number and text from a specific text format
body: <p>I have a text similar to this:</p>
  
  <blockquote>
    <p>Hello @[123456:Foo]</p>
  </blockquote>
  
  <p>How to get '123456' and 'Foo' ?</p>
  
  <p>My attempt:</p>
  
  <pre><code>@\[([\d+]):([\s+])\]
  </code></pre>