diff --git a/src/components/viz/D3.vue b/src/components/viz/D3.vue
index 85a6b33..2c1a50d 100644
--- a/src/components/viz/D3.vue
+++ b/src/components/viz/D3.vue
@@ -1,5 +1,5 @@
 <template lang="pug">
-div
+.card
   button#zoomin +
   svg#tree
     // preserveAspectRatio="xMinYMin meet">