WP Repo Releases renders its output using CSS classes on containers. This allows you to customize the styling of each rendered component. You can find a list of CSS classes here:

• wp-repo-releases_error: Container of any visible plugin error. It can make sense to apply a display: none on this to hide errors from your users.
• wp-repo-releases_empty: Container if no release has been found.
• wp-repo-releases_release: Container of a release. This container contains:
  • An a tag (selectable by CSS selector .wp-repo-releases_release > a:first-child) containing the selected headline level tag with the release’s name.
  • An i tag containing the release date.
  • Another a tag (selectable by CSS selector .wp-repo-releases_release > a:last-child) containing the download link.