chore: math works with math wrappers.

Author: chrisspiegl

assets/scss/style.scss

@@ -1,6 +1,6 @@
 // $content-width: 640px;
 $content-width: 980px;
-$break-mobile: $content-width / 2;
+$break-mobile: calc($content-width / 2);
 // @import url('https://fonts.googleapis.com/css?family=Vollkorn:400,400i,700,700i&display=swap');
 @import url('https://fonts.googleapis.com/css2?family=Playfair+Display:ital,wght@0,400..900;1,400..900&display=swap');