Restriction: You need to have access to an administrator-account in order to change the login page branding.

User menu > Account > Branding

How to customize your Branding

Customize the login screen to your desired branding.
The dashed white frames indicate the areas that can be changed.

Note: If you use a background image that is bright at the top, you will have difficulty seeing the Site Title and Edit Background buttons. Change the Text & Icons Setting from Light to Dark.
  1. Click in a frame to edit the content.
    You can change the default icon file, logo, site title, welcome text and background image. All changes are displayed on the preview image.
  2. Click Save to apply your changes.