Show text layout patterns on grey preview surface

styleguide.css

@@ -2090,6 +2090,13 @@ section + section {
   gap: var(--spacing-small);
 }
 
+.sg-text-layout-pattern__preview-surface {
+  width: 100%;
+  padding: var(--spacing-large);
+  border-radius: var(--radius-card);
+  background: var(--color-light-grey);
+}
+
 .sg-text-layout-pattern__sample {
   margin: 0;
 }