Examples of websites using
Stratos
(designed by Emmanuel Labard, Yoann Minet, Ilya Ruderman, Irene Vlachou and Yury Ostromentsky and released by Production Type in 2016)
with
Plain
('Plain' is a sans-serif font designed by François Rappo and released by Optimo in 2013. The family consists of 11 individual styles, including regular, italic, and bold weights)