Styling the maintenance page

When you need to perform a massive update to your website, it’s a good practice to put it in maintenance mode.

Drupal allows you to enable maintenance mode and provide a custom message to show to your customers:

Figure 10.1 – The form to configure and enable maintenance mode

The URL of the configuration page shown in Figure 10.1 is /admin/config/development/maintenance. Here, you can enable maintenance mode and set a message. The message text only allows plain strings, and the only dynamic part is @site, which will be replaced with the name of the site (as configured on /admin/config/system/site-information).

Suggestions for the maintenance page are as follows:

• maintenance-page--offline.html.twig: Used when the site is offline due to some internal error, such as a broken database connection
• maintenance-page--front.html.twig: Used for the front page of the site and also for pages such as update...