Fira Sans in action on tonsky.me

.header-1 { font-family: "Fira Sans"; font-size: 28.9px; font-style: normal; font-weight: 200; letter-spacing: normal; line-height: normal; text-transform: none; color: #EDF1F7; }
.content-1 { font-family: "Fira Sans", sans-serif; font-size: 17px; font-style: normal; font-weight: 400; letter-spacing: normal; line-height: 30px; text-transform: none; color: #FFFFFF; }
Fira Sans is available from Font Squirrel, Google Web Fonts and Typekit.
Found by @mikesten on 19 Sep 2018.

Liked by:
@mikesten @Joshua_D_

Fira Sans