refactor: Make styles an array

[Artur-]

To reduce the changes in #12041

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[web-padawan]

Consider keeping original styles as is and instead using something like this:

  static get styles() {
    return [loaderStyles, overlayContentStyles];
  }