Add more variables

sass/components/level.sass

@@ -1,3 +1,5 @@
+$level-item-spacing: ($block-spacing / 2) !default
+
 .level
   @extend %block
   align-items: center
@@ -18,7 +20,7 @@
     .level-item
       &:not(:last-child)
         margin-bottom: 0
-        margin-right: 0.75rem
+        margin-right: $level-item-spacing
       &:not(.is-narrow)
         flex-grow: 1
   // Responsiveness
@@ -41,7 +43,7 @@
   // Responsiveness
   +mobile
     &:not(:last-child)
-      margin-bottom: 0.75rem
+      margin-bottom: $level-item-spacing
 
 .level-left,
 .level-right
@@ -55,7 +57,7 @@
     // Responsiveness
     +tablet
       &:not(:last-child)
-        margin-right: 0.75rem
+        margin-right: $level-item-spacing
 
 .level-left
   align-items: center