ISTWCMS-5905: put padding back when there's a section separator

src/patterns/03-layouts/layout/_layout.scss

@@ -13,10 +13,15 @@
   padding-top: 0;
 }
 
-/* Only apply bottom padding to the last section when there's a background. */
-.card__content section.layout:last-child:not(.uw-section__background-color,.uw-section__background-image) {
+/* Only apply bottom padding to the last section when there's a background or a separator. */
+.card__content section.layout:last-child:not(.uw-section__background-color,.uw-section__background-image,.uw-section-separator--bottom,.uw-section-separator--narrow) {
   padding-bottom: 0;
 }
+@media(min-width: $screen-md) {
+  .card__content section.layout:last-child.uw-section-separator--narrow {
+    padding-bottom: unset;
+  }
+}
 
 .uw-section-spacing {
   &--75 {