Add more variables

sass/components/card.sass

@@ -4,13 +4,18 @@ $card-shadow: 0 2px 3px rgba($black, 0.1), 0 0 0 1px rgba($black, 0.1) !default
 
 $card-header-background-color: transparent !default
 $card-header-color: $text-strong !default
+$card-header-padding: 0.75rem !default
 $card-header-shadow: 0 1px 2px rgba($black, 0.1) !default
 $card-header-weight: $weight-bold !default
 
 $card-content-background-color: transparent !default
+$card-content-padding: 1.5rem !default
 
 $card-footer-background-color: transparent !default
 $card-footer-border-top: 1px solid $border !default
+$card-footer-padding: 0.75rem !default
+
+$card-media-margin: $block-spacing !default
 
 .card
   background-color: $card-background-color
@@ -31,7 +36,7 @@ $card-footer-border-top: 1px solid $border !default
   display: flex
   flex-grow: 1
   font-weight: $card-header-weight
-  padding: 0.75rem
+  padding: $card-header-padding
   &.is-centered
     justify-content: center
 
@@ -40,7 +45,7 @@ $card-footer-border-top: 1px solid $border !default
   cursor: pointer
   display: flex
   justify-content: center
-  padding: 0.75rem
+  padding: $card-header-padding
 
 .card-image
   display: block
@@ -48,7 +53,7 @@ $card-footer-border-top: 1px solid $border !default
 
 .card-content
   background-color: $card-content-background-color
-  padding: 1.5rem
+  padding: $card-content-padding
 
 .card-footer
   background-color: $card-footer-background-color
@@ -63,7 +68,7 @@ $card-footer-border-top: 1px solid $border !default
   flex-grow: 1
   flex-shrink: 0
   justify-content: center
-  padding: 0.75rem
+  padding: $card-footer-padding
   &:not(:last-child)
     border-right: $card-footer-border-top
 
@@ -71,4 +76,4 @@ $card-footer-border-top: 1px solid $border !default
 
 .card
   .media:not(:last-child)
-    margin-bottom: 0.75rem
+    margin-bottom: $card-media-margin