This is a theme for the Leo editor that tries to look like Ubuntu's Yaru theme. The gui elements are styled like Ubuntu's Yaru, while the syntax colouring is styled like Gedit's Tango colour scheme.
To use it, place Yaru.leo in the ~/.leo/themes directory (create it if necessary) and add a node titled "@string theme-name = Yaru" to your myLeoSettings.leo.
This is what it looks like:
