:art: fixing grid span for inbetween cards

vue-theme/src/pages/list.vue

@@ -257,4 +257,6 @@ export default {
             margin: 0 $ms--2 0 0
             .posts.is-grid
                 grid-template-columns: repeat(3, 1fr)
+                .post.inbetween
+                    grid-column: span 3
 </style>