Styling is a very important part of websites, since it defines the look and feel of a website.
In Drupal sites, the styling is defined by the enabled theme of the website. CERN has its own theme to set a common look and feel and identity amongst its websites. The theme is called CERN Theme and constitutes the default theme of Drupal websites at CERN. The theme, and Drupal, is responsive and thus accommodates both computers, tablets, and phones out-of-the-box. A detailed overview of the CERN Theme is available here.
By default, new websites automatically include this theme alongside a number of official CERN-modules.