diff --git a/sass/init/_variables.scss b/sass/init/_variables.scss
index d3f31c0..b7e3e66 100644
--- a/sass/init/_variables.scss
+++ b/sass/init/_variables.scss
@@ -75,7 +75,7 @@ $lucida:          'Lucida Grande', 'Lucida Sans Unicode', Lucida, Verdana, sans-
 $futura:          Futura, 'Century Gothic', AppleGothic, sans-serif;
 
 // System-ui font stack.
-$system-ui:       system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "Roboto", "Oxygen", "Ubuntu", "Cantarell", "Fira Sans", "Droid Sans", "Helvetica Neue", sans-serif;
+$system-ui:       system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue', sans-serif;
 
 // Monospace font stacks.
 // For an explanation of why "sans-serif" is at the end of this list, see