Site Tagline Block
The Site Tagline Block allows you to add or update the tagline for your site. Adding this block to your content will display the site tagline and will be more useful once you can edit your Theme’s templates.
The site tagline describes, in a few words, what your site is about. The tagline is sometimes shown in your site header, near your logo, but that depends entirely on your theme. The tagline will sometimes also be used for SEO purposes and can be displayed in search results or on the browsers tab. The Tagline can also be changed on the Settings > General page.
Once you've added the block, there are further options available in the Settings Sidebar including an option to select the font size, color and background color.