Some of our themes include multiple (as we call them) preset schemes, which can customize more than just the colors (they also change fonts, text sizes, example images and even appearance and layout specifics).
Roseta has one such scheme beside the default, which is also available for the free edition of the theme as a separate child theme named Codex. You can preview its general appearance and look on WordPress.org: https://wordpress.org/themes/codex/