misc: distribute SourceSansPro font (#23314)

README

@@ -49,6 +49,12 @@ copyright notices:
   # Licensed under the SIL Open Font License v1.10
   # https://www.fontsquirrel.com/license/d-din
 
+* Source Sans Pro
+  # https://www.fontsquirrel.com/fonts/source-sans-pro
+  #
+  # Licensed under the SIL Open Font License v1.10
+  # https://www.fontsquirrel.com/fonts/source-sans-pro
+
 ~~~~
 
 Some CSS variant files have their own specific licenses.

static/includes/_font-source-sans-pro.scss

@@ -0,0 +1,22 @@
+$source-sans-pro-font-path: '../fonts/SourceSansPro' !default;
+
+@mixin source-sans-pro-font($type, $weight, $style: normal) {
+	@font-face {
+		font-family: 'SourceSansPro-#{$type}';
+		src: url('#{$source-sans-pro-font-path}/SourceSansPro-#{$type}.otf') format('opentype');
+		font-weight: $weight;
+		font-style: $style;
+	}
+}
+
+@mixin source-sans-pro-font-pair($type, $weight) {
+	@include source-sans-pro-font($type, $weight);
+	@include source-sans-pro-font(#{$type}It, $weight, italic);
+}
+
+@include source-sans-pro-font-pair('ExtraLight', 200);
+@include source-sans-pro-font-pair('Light', 300);
+@include source-sans-pro-font('Regular', 400);
+@include source-sans-pro-font-pair('Semibold', 500);
+@include source-sans-pro-font-pair('Bold', 700);
+@include source-sans-pro-font-pair('Black', 900);