use new Fira fonts; use local fonts, fallback to network fonts

Author: cvan

hearth/media/css/lib.styl

@@ -72,11 +72,7 @@ $btn-b-dark = #267CC2;
 $btn-b-lite = saturate(spin($btn-b, 4), 4%);
 
 // Font Stacks
-// TODO: When the Firefox OS devices have a version of "Feura Sans" that actually has as many weights
-// as does FeuraSansWeb then use "Feura Sans." Until then, always load the `font-face`.
-// TODO(cvan): File a bug against Firefox that it shouldn't download unused `font-face`s that are
-// fallbacks.
-$open-stack = FeuraSansWeb, "Open Sans", "Helvetica Neue", Arial, sans-serif;
+$open-stack = "Fira Sans", "Helvetica Neue", Arial, sans-serif;
 
 // Retina
 $retina = unquote('screen and (-webkit-min-device-pixel-ratio: 2), screen and (min--moz-device-pixel-ratio: 2), screen and (min-device-pixel-ratio: 2)');
@@ -360,7 +356,7 @@ fatten() {
 }
 
 glow($glowColor, $glowSize) {
-    box-shadow: 0 0 $glowSize 0 $glowColor; 
+    box-shadow: 0 0 $glowSize 0 $glowColor;
 }
 
 alt-btn-hover-focus() {

hearth/media/css/typography.styl

@@ -1,35 +1,55 @@
 @import 'lib';
 
 @font-face {
-    font-family: 'FeuraSansWeb';
-    src: url('../fonts/FeuraSans/FeuraSansWeb-Light.woff') format('woff'),
-         url('../fonts/FeuraSans/FeuraSansWeb-Light.svg#FeuraSansWebLight') format('svg');
+    src: local('Fira Sans OT Light Regular'),
+         local('Fira Sans Light Regular'),
+         local('Fira Sans OT Light'),
+         local('Fira Sans Light'),
+         local('Fira Sans OT'),
+         local('Fira Sans'),
+         url('../fonts/FiraSans/firasansot-light-webfont.woff') format('woff'),
+         url('../fonts/FiraSans/firasansot-light-webfont.ttf') format('truetype'),
+         url('../fonts/FiraSans/firasansot-light-webfont.svg#fira_sans_otlight') format('svg');
+    font-family: 'FiraSans';
     font-weight: 300;
-    font-style: normal;
 }
 
 @font-face {
-    font-family: 'FeuraSansWeb';
-    src: url('../fonts/FeuraSans/FeuraSansWeb-Regular.woff') format('woff'),
-         url('../fonts/FeuraSans/FeuraSansWeb-Regular.svg#FeuraSansWebRegular') format('svg');
+    src: local('Fira Sans OT Regular'),
+         local('Fira Sans Regular'),
+         local('Fira Sans OT'),
+         local('Fira Sans'),
+         url('../fonts/FiraSans/firasansot-regular-webfont.woff') format('woff'),
+         url('../fonts/FiraSans/firasansot-regular-webfont.ttf') format('truetype'),
+         url('../fonts/FiraSans/firasansot-regular-webfont.svg#fira_sans_otregular') format('svg');
+    font-family: 'Fira Sans';
     font-weight: 400;
-    font-style: normal;
 }
 
 @font-face {
-    font-family: 'FeuraSansWeb';
-    src: url('../fonts/FeuraSans/FeuraSansWeb-Medium.woff') format('woff'),
-         url('../fonts/FeuraSans/FeuraSansWeb-Medium.svg#FeuraSansWebMedium') format('svg');
+    src: local('Fira Sans OT Medium Regular'),
+         local('Fira Sans Medium Regular'),
+         local('Fira Sans OT Medium'),
+         local('Fira Sans Medium'),
+         local('Fira Sans OT'),
+         local('Fira Sans'),
+         url('../fonts/FiraSans/firasansot-medium-webfont.woff') format('woff'),
+         url('../fonts/FiraSans/firasansot-medium-webfont.ttf') format('truetype'),
+         url('../fonts/FiraSans/firasansot-medium-webfont.svg#fira_sans_otregular') format('svg');
+    font-family: 'Fira Sans';
     font-weight: 500;
-    font-style: normal;
 }
 
 @font-face {
-    font-family: 'FeuraSansWeb';
-    src: url('../fonts/FeuraSans/FeuraSansWeb-Bold.woff') format('woff'),
-         url('../fonts/FeuraSans/FeuraSansWeb-Bold.svg#FeuraSansWebBold') format('svg');
+    src: local('Fira Sans OT Bold'),
+         local('Fira Sans Bold'),
+         local('Fira Sans OT'),
+         local('Fira Sans'),
+         url('../fonts/FiraSans/firasansot-bold-webfont.woff') format('woff'),
+         url('../fonts/FiraSans/firasansot-bold-webfont.ttf') format('truetype'),
+         url('../fonts/FiraSans/firasansot-bold-webfont.svg#fira_sans_otbold') format('svg');
+    font-family: 'Fira Sans';
     font-weight: 600;
-    font-style: normal;
 }
 
 body {