Add font-weight-medium to marketing styles, and use it in the type scale (#1497)

* Add and use medium

* Use $font-weight-extrabold instead of hard-coded 800 weight

* Formatting

* Create forty-buses-serve.md

* Add text-medium utility

* Add $font-weight-extrabold

* Bump extra bold to 800

Author: tobiasahlin

.changeset/forty-buses-serve.md

@@ -0,0 +1,5 @@
+---
+"@primer/css": minor
+---
+
+Add font-weight-medium to marketing styles, and use it in the type scale.

src/marketing/support/variables.scss

@@ -3,11 +3,14 @@
 $marketing-font-path: "/fonts/" !default;
 
 $font-mktg: $body-font !default;
+$font-weight-medium: 450 !default;
+$font-weight-extrabold: 800 !default;
+
 $mktg-font-feature-settings: 'ss02' on, 'ss01' on !default;
 $mktg-header-spacing-large: -0.03em !default;
 $mktg-header-spacing-default: -0.01em !default;
 $mktg-header-spacing-threshold: 48px !default;
-$mktg-header-weight-large: 800 !default;
+$mktg-header-weight-large: $font-weight-extrabold !default;
 $mktg-header-weight-default: $font-weight-bold !default;
 $mktg-header-weight-threshold: 24px !default;
 

src/marketing/type/typography.scss

@@ -27,9 +27,11 @@
       @include breakpoint(md) {
         font-size: map-get($pairing-md, "size") !important;
         line-height: map-get($pairing-md, "lh") !important;
+
         @if (map-get($pairing-md, "size") >= $mktg-header-spacing-threshold and map-get($pairing, "size") < $mktg-header-spacing-threshold) {
           letter-spacing: $mktg-header-spacing-large !important;
         }
+
         @if (map-get($pairing-md, "size") >= $mktg-header-weight-threshold and map-get($pairing, "size") < $mktg-header-weight-threshold) {
           font-weight: $mktg-header-weight-large !important;
         }
@@ -40,9 +42,11 @@
       @include breakpoint(lg) {
         font-size: map-get($pairing-lg, "size") !important;
         line-height: map-get($pairing-lg, "lh") !important;
+
         @if (map-get($pairing-lg, "size") >= $mktg-header-spacing-threshold and map-get($pairing-md, "size") < $mktg-header-spacing-threshold) {
           letter-spacing: $mktg-header-spacing-large !important;
         }
+
         @if (map-get($pairing-lg, "size") >= $mktg-header-weight-threshold and map-get($pairing-md, "size") < $mktg-header-weight-threshold) {
           font-weight: $mktg-header-weight-large !important;
         }
@@ -78,11 +82,13 @@
       @include breakpoint(md) {
         font-size: map-get($pairing-md, "size") !important;
         line-height: map-get($pairing-md, "lh") !important;
+
         @if (map-get($pairing-md, "size") >= $mktg-body-spacing-threshold and map-get($pairing, "size") < $mktg-body-spacing-threshold) {
           letter-spacing: $mktg-body-spacing-large !important;
         }
+
         @if (map-get($pairing-md, "size") >= $mktg-body-weight-threshold and map-get($pairing, "size") < $mktg-body-weight-threshold) {
-          font-weight: $font-weight-semibold;
+          font-weight: $font-weight-medium;
         }
       }
     }
@@ -91,17 +97,23 @@
       @include breakpoint(lg) {
         font-size: map-get($pairing-lg, "size") !important;
         line-height: map-get($pairing-lg, "lh") !important;
+
         @if (map-get($pairing-lg, "size") >= $mktg-body-spacing-threshold and map-get($pairing-md, "size") < $mktg-body-spacing-threshold) {
           letter-spacing: $mktg-body-spacing-large !important;
         }
+
         @if (map-get($pairing-lg, "size") >= $mktg-body-weight-threshold and map-get($pairing-md, "size") < $mktg-body-weight-threshold) {
-          font-weight: $font-weight-semibold;
+          font-weight: $font-weight-medium;
         }
       }
     }
   }
 }
 
+.text-medium {
+  font-weight: $font-weight-medium !important;
+}
+
 // Pullquote
 
 @mixin pullquote {