A newer, flatter GTK theme will ship as part of Linux Mint 18 ?Sarah.?

Showing off progress made on the theme in a new blog post, project lead Clement Lefebvre says the new ?Mint Y? theme is inspired by recent design trends towards flatter UI elements. It is based off of the (incredibly) popular Arc GTK theme.

Mint users content with the current design do not need to panic, though.

Although the newer, flatter theme is to ship as part of the next major release of the Ubuntu-based Linux distribution it won't be the default system theme